physics7ar.files.wordpress.com · web view(c) if the same experiment is carried out on earth, air...
TRANSCRIPT
Name: _______________________________________________
Momentum
Date:
Time: Total marks available: Total marks achieved: ______
1
Questions
Q1.
The diagram shows a roller-coaster ride.
The car is pulled slowly from the start to point B and then released.
(a) Choose letters from the diagram to complete this sentence.
(2)The car has the most gravitational potential energy at point .......................................
and it goes fastest at point ....................................... .
(b) The mass of the car is 900 kg.
The maximum speed of the car is 15 m/s.(i) State the relationship between momentum, mass and velocity.
(1)
(ii) Calculate the maximum momentum of the car.Give the unit.
(3)
maximum momentum = ........................... unit ...........................
(iii) State the equation linking kinetic energy (KE), mass and speed.(1)
(iv) Calculate the maximum KE of the car.(2)
2
(Total for question = 9 marks) Q2.Some quantities are vectors, others are scalars.
(a) Complete the table ticking the boxes to show which quantities are vectors and which are scalars.
One has been done for you.(2)
(b) A car travels at 20 m/s.The mass of the car is 1500 kg.
(i) State the equation linking momentum, mass and velocity.(1)
(ii) Calculate the momentum of the car.(2)
momentum = ........................................................... kg m/s
(c) In a crash test, a car runs into a wall and stops.
3
The momentum of the car before the crash is 22500 kg m/s.The car stops in 0.14 s.(i) Calculate the average force on the car during the crash.
(2)
average force = ........................................................... N
(ii) Use ideas about momentum to explain how seat belts can reduce injuries to passengers during a crash.
(3) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 10 marks)Q3.An aeroplane takes two minutes to travel the short distance between airports on two islands.
The graph shows how the speed of the aeroplane changes as it4
takes off flies across the sea lands on the other island When it is flying across the sea, the aeroplane travels at a constant speed.
(a) Use the graph to answer the following questions.(i) State the value of the constant speed.
(1)
speed ...................................... m/s
(ii) Calculate the acceleration of the aeroplane at the start of the journey and give the unit.(3)
acceleration = ...................................... unit ......................................
(iii) Calculate the total distance that the aeroplane travels.(3)
distance = ...................................... m
(b) Each airport has a runway that is about 500 m long.When it lands, the speed of the aeroplane is 40 m/s.
Explain why the airline should not use an aeroplane that has more mass andneeds a higher speed for landing.
(3) ..............................................................................................................................................
5
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
.............................................................................................................................................. (Total for question = 10 marks)
Q4.The driver of a car sees an obstacle in the road and stops the car as quickly as possible.
The car stops without hitting the obstacle.
State three factors that could have affected the stopping distance of the car.
(3)1 ..........................................................................................................................................
.............................................................................................................................................
2 ..........................................................................................................................................
.............................................................................................................................................
3 ..........................................................................................................................................
.............................................................................................................................................
(Total for question = 3 marks)Q5.This question is about collisions.
The diagram shows ball A moving in the direction shown by the arrow.
Ball A collides with ball B, a stationary ball of the same mass and size as ball A.
(a) State the principle of conservation of momentum.
(1) .............................................................................................................................................
.............................................................................................................................................
(b) Ball A collides with ball B. before the collision, ball A moves with a velocity of 10 m/s after the collision, ball B moves in the same direction as ball A with a velocity of 8 m/s ball A continues to move in the same direction, but at a lower velocity
Calculate the velocity of ball A after the collision. 6
[mass of each ball = 0.16 kg](3)
velocity of ball A = ........................................................... m/s
(c) During the collision some kinetic energy is lost.Calculate the kinetic energy lost in the collision.
(3)
kinetic energy lost = ........................................................... J
(Total for question = 7 marks)
Q6.A bowling ball rolls for 3 s and hits a pin.
The graph shows how the velocity of the ball changes with time.
7
(a) How can the graph be used to find the distance that the ball rolls before it hits the pin?(1)
.............................................................................................................................................. ..............................................................................................................................................(b) The mass of the ball is 6.4 kg.
(i) State the equation linking momentum, mass and velocity.(1)
(ii) Calculate the momentum of the ball before it hits the pin.Give the unit.(3)
Momentum = ........................................................... Unit ...........................................................
(c) (i) What is the velocity of the ball after it hits the pin?(1)
8
Velocity = ........................................................... m/s
(ii) After the collision, the ball and the pin have the same velocity.Calculate the mass of the pin.
(3)
Mass = ........................................................... kg
(Total for question = 9 marks)Q7.A student investigates terminal velocity.She uses a tall glass tube filled with oil.
She drops a metal ball into the tube.The ball falls through the oil.
(a) Use ideas about forces to explain how a falling object can reach a terminal velocity.
(5) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
9
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(b) Describe how the student could find out if the ball reaches terminal velocity as it falls through the oil.
In your answer, you should include the measuring instruments that the student will need the measurements that she should take how she could use her measurements to find out if the ball reached terminal velocity.You may include a labelled diagram in your answer.
(5)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
10
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 10 marks)Q8.A rabbit runs across the road in front of a car.
The driver applies the brakes.
State four factors that affect the chance of the rabbit escaping without being hit.
(4)
1 ..............................................................................................................................................
..............................................................................................................................................
2 ..............................................................................................................................................
..............................................................................................................................................
3 ..............................................................................................................................................
..............................................................................................................................................
4 ..............................................................................................................................................
..............................................................................................................................................
(Total for question = 4 marks)
11
Q9.The graph shows the minimum stopping distances, in metres, for a car travelling atdifferent speeds on a dry road.
(a) Complete the equation to show the link between stopping distance, thinkingdistance and braking distance.
(1)Stopping distance=...............................................................................................................
(b) Describe the patterns shown in the graph.(2)
.............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(c) Use the graph to estimate the stopping distance for a car travelling at 35 miles per hour.(1)
Stopping distance = ........................................................... m
(d) To find the minimum stopping distance, several different cars were tested.
Suggest how the data from the different cars should be used to give the values in the graph.(1)
.............................................................................................................................................. (e) The tests were carried out on a dry road.
If the road is icy, describe and explain what change there would be, if any, to(i) the thinking distance
(2) ..............................................................................................................................................
12
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(ii) the braking distance(2)
.............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(Total for question = 9 marks)Q10.A hot-air balloon is tied to the ground by two ropes.
The diagram shows the forces acting on the balloon.
The tension T in each rope is 200 N.
The ropes are untied and the balloon starts to move upwards.
(a) State the value of the force acting downwards on the balloon immediately after the ropes are untied and before the balloon starts moving.
13
(1) force downwards = ........................................................... N
(b) (i) State the relationship between unbalanced force, mass and acceleration.
(1)
(ii) The balloon has a total mass of 910 kg.The initial unbalanced force on the balloon is 400 N upwards.Calculate the initial acceleration.
(2)
initial acceleration = ........................................................... m/s2
(c) Explain how the upward acceleration of the balloon changes during the first few seconds of its flight.
(3) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(d) While the balloon is still accelerating, the pilot controls the balloon by pouring some sand from the bags.
Explain how this affects the upward acceleration of the balloon.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 9 marks) Q11.An ice skater throws a 0.23 kg snowball with a velocity of 13 m/s.
14
(a) (i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the initial momentum of the snowball.(2)
initial momentum = ....................................... kg m/s
(b) When the skater throws the snowball forwards, she slides backwards on the ice.
Explain why she moves in this direction.(3)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(c) The skater wears soft knee pads that compress easily.
Explain how the pads protect her knees when she falls on the ice.(3)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
15
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 9 marks)
Q12.The diagram shows the driving force on a sports car as it moves along a race track.
(a) Name two forces that oppose the driving force. ..............................................................................................................................................
..............................................................................................................................................
(b) The car has a mass of 1400 kg.The acceleration of the car is 5.5 m/s2.(i) State the equation linking force, mass and acceleration.
(1)
(ii) Calculate the force causing this acceleration.(2)
Force = ........................................................... N
(c) Graph 1 shows how the velocity of the car changes with time.
16
Calculate the distance that the car travels in the first four seconds.(3)
Distance = ........................................................... m
(d) As the car travels further along the track, its acceleration changes as shown in graph 2.
17
(i) Which feature of graph 2 shows that the acceleration changes?(1)
..............................................................................................................................................(ii) The acceleration changes even though the driving force does not change.
Suggest two possible reasons for this change in acceleration.(2)
.............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
(Total for question = 11 marks)
Q13.The diagram shows an air track that can be used to investigate motion.
Air comes out through a series of small holes in the air track.18
A small glider floats on a cushion of air.
(a) (i) The diagram below shows the glider at rest on the air track.
Complete the diagram to show the forces acting on the glider.Label the forces.One force arrow has been drawn for you.
(3)
(ii) Explain what effect the cushion of air has on the movement of the glider.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(b) Two light gates connected to a data logger are placed above the air track so that the card will pass through them.
The glider moves at a constant speed to the right.
19
The length of the card is 8.3 cm.The card takes 314 ms to pass through the first light gate.(i) State the relationship between average speed, distance moved and time taken.
(1)
(ii) Calculate the average speed of the card as it passes through the first light gate.(2)
average speed = .................................................. cm/s
(iii) State the time taken for the card to pass through the second light gate.(1)
time taken = .................................................. ms
(Total for question = 9 marks) Q14.A student investigates friction between a block of wood and different types of surface.
(a) The student uses the equipment shown in photograph A to measure the force needed to move the block of wood.
20
(i) Suggest why the student places masses on the block.(1)
..............................................................................................................................................
..............................................................................................................................................
(ii) Explain why he keeps the masses constant during the experiment.(1)
..............................................................................................................................................
..............................................................................................................................................
(b) The student investigates five different types of surface.The table shows his results.
(i) Give an example of a non-continuous variable in this investigation.(1)
.............................................................................................................................................. ..............................................................................................................................................
(ii) Complete the table by inserting the missing average.(1)
(iii) Display the average force results for this investigation on the grid.(4)
21
(c) The student compares his results with others in the class.He finds that they have different values for the forces.Suggest why.
(2) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................(d) The student repeats the investigation using another block of wood as shown in photograph B.
This block of wood has the same mass but a different area of contact.Explain how this change affects the pressure on the surface.
(2) ..............................................................................................................................................
22
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................(e) Suggest two ways in which the student could reduce friction between the two surfaces.
(2) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(Total for question = 14 marks)Q15.A student investigates the motion of a 10 cm square piece of card as it falls.
He attaches some weights to the bottom of the card to make sure it falls vertically.
(a) Add an X to the diagram to show the position of the centre of gravity after the weights have been attached.
(1)(b) The student writes this plan for his investigation.
Which of these is the dependent variable in the student's investigation?(1)
23
A the final speed of the card B the initial height of the card C the initial speed of the card D the mass of the card
(c) The table shows the student's results.
(i) Complete the table by calculating the missing average. Give your answer to two decimal places.(2)
(ii) Plot a graph to show how the average final speed changes with height.(4)
(iii) Circle the anomalous point on the graph.(1)
(iv) Add a curve of best fit to the graph.24
(1)(v) Describe the relationship between height and average final speed.
(2) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(d) The photograph shows the student releasing a card.
Give two ways that the student could improve the accuracy of his measurements.(2)
1 ..........................................................................................................................................
.............................................................................................................................................
2 ..........................................................................................................................................
.............................................................................................................................................
(Total for question = 14 marks) Q16.The photograph shows a fruit seller using a yard-arm to weigh fruit.
25
The yard-arm consists of a steel bar about 1 m long, with a basket at one end and a moveable weight at the other end.
It is held up by a hook which is fixed to the bar close to the basket.
The diagram shows a yard-arm being used to find the weight of five bananas.
(a) Draw an X on the diagram to show the pivot point.
(1)(b) State the principle of moments.
(1) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(c) The support for the basket is 14.1 cm from the pivot.
The moveable weight is 84.6 cm from the pivot and weighs 1.25 N.Calculate the weight of the five bananas.
26
[ignore weight of steel rod and basket](3)
weight of five bananas = ........................................................... N
(d) Calculate the mass in grams of one banana.
(3)
mass of one banana = ........................................................... g
(e) Suggest two ways that the fruit seller could alter his yard-arm so that he could measure larger weights.
(2)1 ..........................................................................................................................................
.............................................................................................................................................
2 ..........................................................................................................................................
.............................................................................................................................................
(Total for question = 10 marks) Q17.The diagram shows a man pulling a child on a sledge.
(a) The acceleration of the sledge is 1.5 m/s2.
27
The mass of the child and sledge is 38 kg.(i) State the equation linking force, mass and acceleration.
(1)
(ii) Calculate the force needed to produce this acceleration.(2)
force = ............................................... N
(iii) Suggest a reason why the force exerted on the sledge by the man must be greater than the force calculated.
(1).............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(b) The sledge starts from rest and accelerates at 1.5 m/s2 until its velocity is 2.8 m/s.
(i) State the relationship between acceleration, velocity and time.(1)
(ii) Show that the time taken to reach 2.8 m/s is about 2 s.(2)
(c) This velocity-time graph shows the motion of the sledge as it travels down a hill.
28
(i) Calculate the distance travelled by the sledge.(3)
distance travelled = ......................................... m
(ii) State the equation linking average speed, distance moved and time taken.(1)
(iii) Calculate the average speed of the sledge for the whole journey.(2)
average speed = ..........................................m/s
(Total for question = 13 marks) Q18.A student wants to use a weighing scale to find the weight of her school bag.
She has a weighing scale marked in kilograms instead of newtons.
The weighing scale is not working properly.
29
With nothing hanging from it, the weighing scale shows 1.5 kg.
(a) What is the weight of a 1.5 kg mass?(1)
Weight = ........................................................... N(b) The student decides to check the weighing scale.
She has no accurate weights.Instead, she puts some tins of beans in a plastic bag and hangs it from the scale.
30
Her readings are shown in the table.
(i) Draw a graph to show how the scale reading varies with the number of tins ofbeans.
(5)
31
(ii) Circle the anomalous point on your graph.(1)
(c) The student notices that the label on each tin says 'contains 0.4 kg of beans'.She remembers that six tins of beans gave a scale reading of 3.9 kg.
32
She hangs her school bag from the weighing scale.The scale reading is 5.0 kg.She also concludes that her school bag must have a mass of exactly 3.5 kg.Suggest reasons why the student's conclusions might be incorrect.
(4) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
.............................................................................................................................................. (Total for question = 11 marks)Q19.(a) A student measures the weight of a cannonball as 50 N.
(i) Name a piece of equipment he could use to measure the weight.(1)
.............................................................................................................................................
(ii) State the equation relating weight, mass and g.(1)
(iii) Calculate the mass of the cannonball.(2)
mass ........................................................... kg
(b) Describe how the student could find the density of the cannonball.
33
You should include details of any further measurements he would need to make.(3)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(c) A cannonball is fired from a cannon.
When the cannonball is fired, the cannon moves in the opposite direction, as shown in the diagram.
Using ideas about momentum, explain why the cannon moves in the opposite direction to the cannonball.
(3) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 10 marks) Q20.Scientists test the safety features of a car by crashing it into a large block of concrete.
A dummy is placed in the driver's seat and the scientists video the crash.
34
(a) In one test, the dummy and the car travel at 8 m/s.The mass of the dummy is 72 kg.Calculate the momentum of the dummy.
(2)
Momentum = ........................................................... kg m/s
(b) In another test, the momentum of the dummy changes by 920 kg m/s in a time of 0.17 s.Calculate the average horizontal force acting on the dummy during this time.
(2)
Average force = ........................................................... N(c) These tests help to make our roads safer.
(i) State two factors that affect the stopping distance of a car driven on a road.(2)
1 .....................................................................................................................................................................
..............................................................................................................................................2 .....................................................................................................................................................................
..............................................................................................................................................(ii) Use ideas about momentum to explain how the crumple zone of a car helps toreduce injuries during a crash.
(3) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
35
..............................................................................................................................................
..............................................................................................................................................
.............................................................................................................................................. (Total for question = 9 marks)Q21.(a) A boy of mass 43.2 kg runs and jumps onto a stationary skateboard.
The boy lands on the skateboard with a horizontal velocity of 4.10 m/s.(i) State the relationship between momentum, mass and velocity.
(1)
(ii) The skateboard has a mass of 2.50 kg.Using ideas about conservation of momentum, calculate the combined velocity of the boy and skateboard just after the boy lands on it.
(4)
combined velocity = ........................................................... m/s
(b) The boy holds a heavy ball as he stands on a stationary skateboard.
The boy throws the ball forwards while still standing on the skateboard.
36
Explain what happens to the boy and the skateboard.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 7 marks) Q22.A student is playing a game with some empty tins.
(a) He throws a wet cloth of mass 0.15 kg at the tins.The wet cloth moves at a velocity of 6.0 m/s.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the wet cloth and give the unit.(3)
Momentum = ........................................................... unit. ...........................................................
(iii) The wet cloth sticks to tin 1.
37
The mass of tin 1 is 0.050 kg.The cloth and tin 1 move away together. Calculate their velocity.(2)
Velocity = ........................................................... m/s(b) The student throws a bigger wet cloth at the remaining tins.
This wet cloth sticks to tins 2 and 3 and they move away together.
The student concludes
38
Do you agree with this conclusion?Explain why.
(2) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
.............................................................................................................................................. (Total for question = 8 marks)Q23.A lorry carries a load of hot asphalt – a runny mixture of small stones and tar.
(a) The mass of the lorry and its load is 17 000 kg.The velocity is 13 m/s.
(i) State the equation linking momentum, mass and velocity.(1)
(ii) Calculate the total momentum of the lorry and its load.(2)
momentum = ........................................................... kg m/s
39
(b) The lorry stops suddenly and the load slides to the front, as shown below.
Force A and force B are upward forces from the road on the lorry.(i) Use ideas about momentum to explain why the load slides to the front whenthe lorry stops suddenly.
(2) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................(ii) Use ideas about moments to explain why force B increases when the load slides to the front.
(3) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
.............................................................................................................................................. (c) The force on the road from one of the tyres is 53 000 N.
The pressure of the air in this tyre is 390 kPa.(i) State the equation linking pressure, force and area.
(1)
(ii) Calculate the area of this tyre in contact with the road.(2)
40
Area = ........................................................... m2
(Total for question = 11 marks)Q24.Some cars have a pedestrian airbag for safety.
If a pedestrian is hit and lands on the front of the car, the airbag inflates.
Use ideas about momentum to explain how this airbag can reduce injuries to pedestrians.
(4)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for Question = 4 marks)
41
Q25.The diagram shows a box attached to a parachute, falling at constant velocity.
(a) State the name for this constant velocity.
(1) .............................................................................................................................................
(b) Explain, in terms of forces, why the box and parachute fall at constant velocity.
(4) .............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 5 marks)
42
Q26.Newton's Cradle consists of a set of identical solid metal balls hanging by threadsfrom a frame so that they are in contact with each other.
(a) A student initially pulls ball A to the side as shown.The student releases ball A and it collides with ball B.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Each ball has a mass of 100 g.At the time of collision, ball A has a velocity of 3m/s.Calculate the momentum of ball A at the time of impact and give the unit.
(3)
momentum ........................................................... unit ...........................................................
(iii) After the collision, ball A stops. Ball E moves away. The other balls remain still.
The momentum of ball E as it moves away is the same as the momentum of ball A at the time of impact.Give the reason for this.
43
(1) .............................................................................................................................................. ..............................................................................................................................................
(b) The student then releases balls A and B together as shown below.
Predict what will happen to the other balls after the collision and give a reason foryour answer.
(2) .............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(Total for question = 7 marks)Q27.The photograph shows a hammer just before it hits a nail.
(a) The mass of the hammer is 0.50kg.
When it hits the nail, the hammer is travelling downwards with a velocity of 3.1m/s.(i) State the relationship between momentum, mass and velocity.
44
(1)
(ii) Calculate the momentum of the hammer.(2)
momentum = ........................................................... kg m/s
(iii) The hammer stops quickly when it hits the nail.The momentum of the hammer reduces to zero in 0.070s.
Calculate the amount of force that causes this to happen.(2)
force = ........................................................... N
(b) As it enters the wood, the nail exerts a force on the wood.
At the same time, the wood exerts a force on the nail.
Explain how these two forces are related.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(c) Both ends of the nail exert pressure when the nail goes into the wood.
45
Explain why the nail exerts more pressure on the wood than it does on the hammer.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 9 marks)
Q28.The table gives some measurements about a raindrop.
(a) (i) State the relationship between momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the raindrop as it hits the ground. Give the unit.(3)
momentum = .............................. unit ..............................
(b) (i) State the equation linking gravitational potential energy, mass, g and height.
46
(1)
(ii) Calculate the change in gravitational potential energy (GPE), when the raindrop falls 1200 m above the ground.
(2)
GPE = ........................................................... J
(iii) State the kinetic energy (KE) of the raindrop as it hits the ground.[assume no energy losses]
(1)
KE = ........................................................... J
(c) (i) State the equation linking kinetic energy, mass and speed.
(1)
(ii) Show that the speed of the raindrop as it hits the ground would be about 150 m/s.[assume no energy losses]
(3)
(iii) Explain why the actual speed of the raindrop as it hits the ground is much less than 150 m/s.(2)
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 14 marks) Q29.(a) Which of these is a scalar quantity?
(1)
A weight
47
B mass
C momentum
D velocity
(b) Which of these is a vector quantity?
(1)
A acceleration
B temperature
C charge
D density
(c) The diagrams show the forces acting on four balls falling in air.
Which diagram shows a ball decelerating as it falls?(1)
(Total for question = 3 marks)Q30.(a) Parachutes are used to slow down a spacecraft as it falls through the atmosphere.
Photograph G shows an Apollo spacecraft with three parachutes attached.
48
This spacecraft falls at a constant velocity.(i) State the name of this constant velocity.
(1) ..............................................................................................................................................
(ii) Explain why this velocity stays at a constant value.(3)
.............................................................................................................................................. ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(iii) Photograph H shows an identical Apollo spacecraft. Only two of its parachutesare working.
Explain how the constant velocity reached by this spacecraft compares withthe constant velocity of the spacecraft shown in photograph G.
49
(2) ..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(b) Photograph I shows a Space Shuttle using a parachute when it lands on a runway.
Explain what would happen to the stopping distance of the Shuttle if this parachute did not open.(2)
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
..............................................................................................................................................
(Total for question = 8 marks)Q31.(a) State the similarity and the difference between scalars and vectors.
(2)
similarity .............................................................................................................................................
.............................................................................................................................................
difference.............................................................................................................................................
.............................................................................................................................................
(b) Complete the table by ticking ( ) the correct boxes to show whether each quantity is a scalar or a vector.
The first one has been done for you.
50
(3)
(Total for Question = 5 marks)
Q32.The diagram shows the horizontal forces on a car travelling to the right along a level road.
(a) How can you tell that the car is accelerating?
(1) .............................................................................................................................................
.............................................................................................................................................
(b) (i) State the relationship between acceleration, change in velocity and time.
(1)
(ii) The car accelerates for 6.0 s.The velocity of the car increases from 15 m/s to 24 m/s.Calculate the acceleration of the car.
(2)
51
acceleration = ........................................................... m/s2
(c) Describe how the horizontal forces on the car change when the driver applies the brakes.
(2) .............................................................................................................................................
.............................................................................................................................................
(Total for question = 6 marks)Q33.A student makes chains of elastic bands by joining them together with paperclips.
He uses a newtonmeter to stretch each chain along a metre rule, as shown in photograph A.
For each chain, he records the number of elastic bands the length when the tension is 2 N the length when the tension is 1 NThen he calculates the difference in length for each chain.
(a) (i) Complete the table by calculating the missing value.(1)
(ii) Use the grid(on the next page) to plot a graph to show the relationship between the number of elastic bands and the difference in length.
(5)
52
(iii) Describe your line of best fit.(2)
.............................................................................................................................................. ..............................................................................................................................................
(b) Photograph B shows a paperclip in one of the chains against the same metre rule.
Use photograph B to estimate the length of this paperclip. (2)
Length = ........................................................... cm53
(c) Look again at photograph A.Suggest two ways that the student could improve his measuring technique.
(2)1 .....................................................................................................................................................................
..............................................................................................................................................
2 .....................................................................................................................................................................
..............................................................................................................................................
(Total for question = 12 marks)Q34.The Apollo 15 mission landed on the Moon in 1971.
The astronaut David Scott dropped a hammer and a feather. They were released from rest at the same time and from the same height. The hammer and the feather landed at the same time.
(a) The graph shows how the velocity of the hammer changed with time.
(i) Use the graph to calculate the acceleration due to gravity on the Moon.Give the unit.(3)
54
Acceleration = ........................................................... Unit ...........................................................
(ii) Use the graph to calculate the height the hammer was dropped from.(2)
Height = ........................................................... m
(b) The gravitational field strength is smaller on the Moon than on the Earth.Suggest why.(1)
..............................................................................................................................................
..............................................................................................................................................(c) If the same experiment is carried out on Earth, air resistance affects both objects.
The feather reaches the ground after the hammer, even though the force of air resistanceis smaller on the feather than on the hammer.
Explain why the feather reaches the ground after the hammer.(4)
.............................................................................................................................................. .......................................................................................................................................................................
.................................................................................................................................................................
................................................................................................................................................................
.................................................................................................................................................................
................................................................................................................................................................
............................................................................................................................................................... (Total for question = 10 marks)Q35.(a) Which of these quantities is a scalar?
(1)
A acceleration
B energy
C force
D velocity
55
(b) The diagram shows the horizontal forces acting on a van at a particular instant, as it accelerates.
(i) Calculate the resultant horizontal force acting on the van.(1)
resultant force = ........................................................... N
(ii) State the equation linking resultant force, mass and acceleration.(1)
(iii) The mass of the van is 2500 kg.Calculate the acceleration of the van.Give the unit.(3)
acceleration = .................................................. unit ..................................................
(c) The graph shows how the velocity of a van changes with time.
Explain the shape of the graph.Use ideas about forces in your answer.
(5) .............................................................................................................................................
56
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
.............................................................................................................................................
(Total for question = 11 marks)
57