4 exams model prep3 mid term science

First Term ScienceAl-Karma Language School Prep 3

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Question (1)

Write the scientific term:

1)- The change of object’s location as time passes according to the location of another object.

(---------------)

2)- It is the change of an object’s speed in one second

(---------------)

3)- It is the rate change of displacement .

(---------------)

4)- It is the light ray that bounces (returns back) from the reflecting surface.

(---------------)

5)- It is the center of the sphere that the mirror is considered a part of diagram So it is in front of the concave mirror or behind the convex mirror.

(----------------)

Question (2)

Give reason for:

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1)- We say that an objects move with irregular speed.

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2)-the incident light ray on a concave mirror passing through the center of curvature reflects on itself.

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3)-the real image can be received on a screen , while the virtual image cannot .

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Question (3)

Complete the following:

1. If car (A) takes a smaller time than car (B) to cover the same distance therefore, car --------- is faster than car ----------.

2)- Uniform acceleration is the change of objects --------------by equal values through ---------------------------- periods of time

3)- --------- is the rate of change of distance, while - ------- is the rate of change of displacement

4 The ……… ….is any straight line that passes by the center of curvature of mirror and any point on its surface expect its pole.

5)- The (distance – time) graph of an object moves at uniform speed is represented by a --------- line passing through ----------- -

Question (4)

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A)- Car moves with average speed 80 Km/h, it covers a distance

between 2 towns at 2 hours calculate distance between 2 cities

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B)- A car moves at speed 40 m/s then the driver use the break to stop the car through 20 sec. Calculate the acceleration of the car?

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Question (1)

1)- Motion. 3


2)-acceleration .

3)-velocity

4)- The reflected light ray.

5)- Center of mirror curvature C

Question (2)

Give reason for:

1 - Because the object covers equal distances at unequal periods of time

or unequal distances at equal periods of time.

2)-because it falls perpendicular to the spherical mirror and the angle of incidence equals zero.

3)-Because the real image is formed in front of the mirror from the intersection of the reflected rays while the virtual image is formed behind the mirror from the intersection of the extension of the reflected ray.

Question (3)

1)- A , B.

2)- speed, equal.

3)- speed ,velocity

4)- secondary axis

5)- straight – origin point.

Question (4)

4


A)-

D= 80 x 2 = 160 km

B)-

a = 0-40/20 = -2 m/sec 2

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Question (1)


1)- An instrument in cars used to identify the speed directly.

(---------------)

2)- It is the change of object’s speed by equal values through equal periods of time.

(---------------)

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3)- It is the displacement covered in 1 second .

(---------------)

4)- It is the angle between the incident light ray and the normal.

(---------------)

5)- It is the Straight line that passes by the pole of the mirror (P) and its center of curvature (C).

(---------------)

Question (2)

Give reason for:

1)- Cars provided with speedometer.

---------------------------------------------------------------------------------------------------------------2)- A convex mirror is put at the left side of the driver of the car.

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3)-To obtain a suitable image for you , you should stand at a distance less than the focal length of a concave mirror.

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Question (3)


2. The two factors necessary for description of movement are ------------- and ------------.

2)- Uniform speed of a moving body means its ------------------- remain constant as ----------- passes.

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First Term ScienceAl-Karma Language School Prep 3 3)- The displacement equals the distance, while the object moves in a direct --- ---- line and in one direction.

4 The… ………mirror is a part of sphere, its inner surface is the reflecting surface and it…… …..light rays after reflection.

5)- When an object moves with decelerating motion, this means that its -- -------- speed is greater than its -- ---- speed.

Question (4)

A)- Calculate time taken by a moving train to cover a distance of 300 Km. if it moves with average speed 60 Km/h.

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B)- An object moves with initial speed =10 m/s if you know that acceleration by which object moves equal 3 m/s2. Calculate its final speed after 5 sec?

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Question (1)

1)- Speedometer.

2)- Uniform acceleration.

3)-velocity.

4)- Angle of incident.

5)- Principal axis of the mirror.

Question (2)

Give reason for:

1)- To help us to identify the speed of cars directly.

2)- Because it forms an erect and smaller image for the way behind The car .

3)-Because the image formed will be virtual , upright ang magnified.

Question (3)

1)- Distance covered by the moving body, time taken to cover this distance.

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2)- speed, time .

3)- straight.

4)- concave – converges.

5)- initial – final.

Question (4)

A)-

T = 300/ 60 = 5 h

B)-

3 = v2 -10 / 5 v2 = 25 m/s

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Question (1)


1)- Represents regular speed by which the moving object moves to cover the same distance at the same time taken to cover this distance.

(---------------)

2)- The change of the object’s speed by equal values through unequal periods of time.

(---------------)

3)- The incident light ray, the reflected light ray and the normal to the surface of reflection at the point of incident all lie on the same plane perpendicular to the reflecting surface.

(---------------)

4)- It is the distance between focus of the mirror [F] and its pole [P].

(---------------)

5)- It is the straight line that passes by the center of curvature of the mirror and any point on its surface except the pole.

(---------------)

Question (2)

Give reason for:

1)- It is hard to measure regular speed of moving car.

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2)- It is difficult to measure the regular speed of a moving car practically.

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3)- Concave mirror is used for solar ovens.

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Question (3)


1)- A car moves 80 m in 4 sec, it moves at speed equals to -----------

2)- The motion of an object can be represented by (-------------------− time) and (----------------− time) graphs.

3)- The straight line joining the object to its image is… ……..to the surface of the mirror.

4)- The image formed by the convex mirror is…… …………………..………..and

…….…… ……………..…than the object.

5 -(Speed is a physical quantity which is used to ----- -- and -- ---------- the movement of objects .

Question (4)

A)- Which of the following moves in higher speed

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a. Train moves at 72 Km/h. b. A bird covers 20 m in one sec.

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B)- A car moves at speed 108 Km/h, if the driver reduces its speed by a rate 3 Km/h2. Calculate the car’s speed after half an hour?

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Question (1)

1)- Average speed.

2)- irregular acceleration.

3)- Second law

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4)- focal length of the mirror.

5)- secondary axis of the mirror.

Question (2)

Give reason for:

1)- Because car speed changes according to traffics.

2)- Because the car's speed changes according to traffic

3)- Because it concentrates sunlight for heating

Question (3)

1)- 80/4= 20 m/s.

2)- (distance- time) and (speed- time).

3)- perpendicular

4)- upright , smaller.

5)- describe – measure.

Question (4)

A)-

Speed of the train = 72x 1000/ 60x60 = 20 m/s

Speed of the bird = 20 m/s …. They move at equal speed

B)-

-3 = v2 – 108 /0.5 v2 = 106.5 Km/hr

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Question (1)


1)- The value of an object’s speed determined in relation to an observer.

(-----------------)

2)- It is the length of the shortest straight line between two position .

(---------------)

3)- Angle of incidence = angle of reflection.

(---------------)

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4)- The mirror which its reflecting surface is a part of the inner surface of the sphere. {It converges or collects light rays}.

(---------------)

5)- It is the point that is in the middle of the reflective surface of the mirror.

(---------------)

Question (2)

Give reason for:

1)- Speed is a scalar quantity, while velocity is a vector quantity.

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2)- When you look at a plane mirror you find that you hold the pen by the left hand which is inverses the real position.

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3)-when you look at a mirror , you see your face image.

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Question (3)


1)- A train moves from Cairo to Banha a distance of 45 Km in 1.5 hours so its average speed equals ----------.

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2)- Measuring units of speed are --------- and / or --------- while measuring unit of acceleration is ----------.

.

3 -(The image formed by a plane mirror for an object is…..……

.……… ……,and ……… ……the object in size .

4 The relative speed depends on the –-------- of the ------ --who determines the speed.

5)- the radius of the concave mirror equals -------- of its focal length

Question (4)

A)- if the angle between the incidence ray and the reflected ray is 140º:

1)-find the angle of incidence and the angle of reflection.

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2)-what is the relation between them?

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B)-the perimeter of the circle is 44 meters and the diameter is 14 meter when an object moves from point (A) to point (B) to point (C) in 10 seconds

1- Calculate the distance =------------

2- Calculate the displacement = -------------

3- Calculate the velocity =-----------

16

C

B

A14 m


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Question (1)

1)- Relative speed

2)- Displacement

3)- First law

4)- concave mirror.

5)- Pole of the mirror (p)

Question (2)

Give reason for:

1)- Because the speed is determined by magnitude only where the velocity is determined by magnitude and direction

2)- Because the images formed by the plane mirror are laterally reversed

3)-due to light reflection

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Question (3)

1)- 45/1.5= 30 km/hour.

2)- m/s , km/ hr , m/s2

3)- reversed, virtual. – equal.

4)- position – observer.

5) twice

Question (4)

A)-

1)- the angle of incidence = angle of reflection = 140º/2 = 70º.

2)-the angle of incidence = angle of reflection.

B)-

1)- Distance = 22 meters

2)- displacement = 14 meters in AC direction

3)- the velocity = displacement / total time = 14/10 = 1.4 m/sec in AC direction

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4 exams model prep3 mid term science

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