Ark Elvin Academy

Year 9 Science Study Pack

Autumn assessment 2017

Name __________________

What I am going to be assessed on?

You will be assessed on everything that you have

been taught since September.

How many exams will I have?

3 x 30 minutes papers

1 Biology exam

1 Chemistry exam

1 Physics exam

Biology

Cell Biology: structure and transport

Part 1: Glossary

1. active transport

the movement of substances from a dilute solution to a more concentrated solution against a concentration gradient, requiring energy from respiration

2. algae simple aquatic organisms (protista) that make their own food by photosynthesis

3. alveoli tiny air sacs in the lungs that increase the surface area for gaseous exchange

4. bacteria single-celled prokaryotic organisms

5. cell membrane the membrane around the contents of a cell that controls what moves in and out of the cell

6. cell wall the rigid structure around plant and algal cells. It is made of cellulose and strengthens the cell

7. cellulose the complex carbohydrate that makes up plant and algal cell walls and gives them strength

8. chlorophyll the green pigment contained in the chloroplasts

9. chloroplasts the organelles in which photosynthesis takes place

10. cytoplasm the water-based gel in which the organelles of all living cells are suspended and most of the chemical reactions of life take place

11. diffusion the spreading out of the particles of any substance in a solution, or particles in a gas, resulting in a net movement of particles from an area of higher concentration to an area of lower concentration down a concentration gradient

12. eukaryotic cells

cells from eukaryotes that have a cell membrane, cytoplasm, and genetic material enclosed in a nucleus

13. hypertonic (osmosis)

a solution that is more concentrated than the cell contents

14. hypotonic (osmosis)

a solution that is less concentrated than the cell contents

15. isotonic (osmosis)

a solution that is the same concentration as the cell contents

16. mitochondria the site of aerobic cellular respiration in a cell

17. nucleus organelle found in many living cells containing the genetic information surrounded by the nuclear membrane

18. osmosis the diffusion of water through a partially permeable membrane from a dilute solution (which has a high concentration of water) to a concentrated solution (with a low concentration of water|) down a concentration gradient

19. partially permeable membrane

a membrane that allows only certain substances to pass through

20. permanent vacuole

space in the cytoplasm filled with cell sap

21. phloem the living transport tissue in plants that carries dissolved food (sugars) around the plant

22. plasmolysis the state of plant cells when so much water is lost from the cell by osmosis that the vacuole and cytoplasm shrink and the cell membrane pulls away from the cell wall

23. prokaryotic cells

from prokaryotic organisms have a cytoplasm surrounded by a cell membrane, and a cell wall that does not contain cellulose. The genetic material is a DNA loop that is free in the cytoplasm and not enclosed by a nucleus. Sometimes there are one or more small rings of DNA called plasmids

24. resolving power

a measure of the ability to distinguish between two separate points that are very close together

25. ribosomes the site of protein synthesis in a cell

26. sperm the male sex cells or gametes that carry the genetic material from the male parent

27. stomata openings in the leaves of plants, particularly on the underside and opened and closed by guard cells, allowing gases to enter and leave the leaf

28. turgor the pressure inside a plant cell exerted by the cell contents pressing on the cell wall

29. ventilated movement of air or water into and out of the gas exchange organ, for example lungs or gills

30. xylem the non-living transport tissue in plants that transports water from the roots to the leaves and shoots

Part 2: Key knowledge

1. Animal and plant cells Key information: Most animal cells have the following parts: a nucleus, cytoplasm, a cell membrane, mitochondria to carry out aerobic respiration which releases energy for the cell, ribosomes to carry out protein synthesis by joining many amino acids. In addition to the parts found in animal cells, plant cells often have: • chloroplasts filled with chlorophyll to absorb light for photosynthesis • a permanent vacuole filled with cell sap to provide support to the cell Plant and algal cells also have a cell wall made of cellulose, which strengthens the cell.

Figure 1: structure of an animal cell Figure 2: structure of plant cell

2. Eukaryotes and prokaryotes Key information: Plant and animal cells (eukaryotic cells) have:

• genetic material enclosed in a nucleus to control the activity of the cell

• a cell membrane to control what enters and exits the cell

• cytoplasm to allow reactions to take place Bacterial cells (prokaryotic cells) are much smaller in comparison. The genetic material is not enclosed in a nucleus. It is a single DNA loop and there may be one or more small rings of DNA called plasmids. They also have cytoplasm, a cell membrane and a cell wall to provide strength and support to the cell.

3. Cell differentiation and specialised cells Key information: Cells may be specialised to carry out a particular function: • sperm cells, nerve cells and muscle cells in animals • root hair cells, xylem and phloem cells in plants.

As an organism develops, cells differentiate to form different types of cells. • Most types of animal cell differentiate at an early stage. • Many types of plant cells can differentiate throughout life. • In mature animals, cell division is mainly restricted to repair and replacement. As a cell differentiates it gets different sub-cellular structures so it can carry out a certain function. It has become a specialised cell.

Figure 3: structure of a prokaryote cell

Figure 4: summary of the structure

and function of specialised cells

4. Microscopes Key information: • A light microscope shines a beam of light across a thin, dead, stained specimen. • The resolution (ability to distinguish between two points) and magnification of a light

microscope is high enough the view the nucleus and cell membrane. • Most organelles are too small to be viewed with a light microscope.

5. Diffusion Key information: Diffusion is the spreading out of the particles of any substance in solution, or particles of a gas, resulting in a net movement from an area of higher concentration to an area of lower concentration.

Figure 5: image of a microscope

Figure 6: equation triangle to calculate magnification

1. Magnification = image size / size of real object

2. Image size = magnification x size of real object

3. Size of real object = image size / magnification

Figure 7: explanation of diffusion in

terms of particles

6. Osmosis and investigating osmosis Key information:

1. Water may move across cell membranes via osmosis. 2. Osmosis is the diffusion of water from a dilute solution to a concentrated solution

through a partially permeable membrane.

Plant tissue can be used to measure the rate of uptake of water in different solutions. During these experiments, only the water moves. Salt and sugar molecules are too large to pass across the partially permeable membranes. The higher the concentration of salt or sugar, the lower the concentration of water.

7. Active transport Key information: Active transport moves substances from a more dilute solution to a more concentrated solution (against a concentration gradient). This requires energy from respiration. Active transport allows mineral ions to be absorbed into plant root hairs from very dilute solutions in the soil. Plants require ions for healthy growth. It also allows sugar molecules to be absorbed from lower concentrations in the gut into the blood which has a higher sugar concentration. Sugar molecules are used for cell respiration.

Figure 8: a model of osmosis in

hypertonic and hypotonic solutions

Figure 9: osmosis in plant cells

Figure 10: the uptake of mineral

ions in roots via active transport

Part 3: Key questions

1. Animal and plant cells

a. Label the cells:

b. Fill in the table with the functions of each organelle.

Organelle Function

Nucleus Cytoplasm Cell membrane Mitochondria

Ribosomes Chloroplasts Vacuole Cell wall

c. Identify three organelles found in plant cells but not animal cells.

2. Eukaryotes and prokaryotes

a. What type of cells are eukaryotic cells

b. What type of cells are prokaryotic cells?

c. Outline 3 differences between prokaryotes and eukaryotes.

3. Cell differentiation and specialised cells

4. Microscopes

a. The image shows human cheek cells. In the space below,

draw a biological drawing of this image. Label the organelles which

are visible.

b. Describe how the slide of cheek cells would have been

prepared.

c. State what is meant by the term resolution.

a. Describe how the structure of a sperm cell relates to its function.

b. Describe how the structure of a root hair cell relates to its function.

c. what is meant by the term ‘differentiation’.

d. Describe why cell division is important for animals.

e. Explain how the xylem is specialised to carry out its function.

f. State the name of the tissue in plants which allows plant cells to differentiate throughout life.

d. Give the equation that links magnification, image size and actual size.

5. Diffusion

a. Define the term ‘diffusion’.

b. Give two examples of molecules which diffuse in and out of cells. Name the process these

molecules are involved in.

c. State three factors that affect the rate of diffusion.

d. Describe the relationship between surface area: volume ratio and the rate of diffusion.

e. Complete the table to show how the following are adapted for exchanging materials.

Organ How it is adapted for exchange Lungs

Small intestine

Gills

Leaves

Roots

6. Osmosis and investigating osmosis

a. Define the term osmosis b. Why is salt water an example of a hypertonic solution? c. In what type of solution would water movement be equal? d. Outline the similarities and differences between osmosis and diffusion

e. Describe why the water moves from the left to the

right side.

f. Explain why the sugar molecules do not move.

7. Active transport a. Outline the main differences between diffusion and active transport.

b. Explain, using examples, the importance of active transport for plant growth.

c. Explain why active transport cannot occur in the absence of oxygen.

d. Describe when active transport is used by the cells lining the small intestine.

Chemistry

Atomic structure

Part 1: Glossary

1. aqueous solution a. the mixture made by adding a soluble substance to water

2. atom b. the smallest part of an element that can still be recognised as that element

3. atomic number c. the number of protons (which equals the number of electrons) in an atom. It is sometimes called the proton number

4. balanced symbol equation

d. a symbol equation in which there are equal numbers of each type of atom on either side of the equation

5. chromatography e. the process whereby small amounts of dissolved substances are separated by running a solvent along a material such as absorbent paper

6. compound f. a substance made when two or more elements are chemically bonded together

7. electron g. a tiny particle with a negative charge. Electrons orbit the nucleus of atoms or ions in shells

8. electronic structure

h. a set of numbers to show the arrangement of electrons in their shells (or energy levels)

9. element i. a substance made up of only one type of atom. An element cannot be broken down chemically into any simpler substance

10. group j. all the elements in the columns (labelled 1 to 7 and 0) in the periodic table

11. ion k. a charged particle produced by the loss or gain of electrons

12. isotope l. atoms that have the same number of protons but different number of neutrons, i.e., they have the same atomic number but different mass numbers

13. law of conservation

14. of mass

m. the total mass of the products formed in a reaction is equal to the total mass of the reactants

15. mass number n. the number of protons plus neutrons in the nucleus of an atom

16. neutron o. a dense particle found in the nucleus of an atom. It is electrically neutral, carrying no charge

17. noble gases p. the very unreactive gases found in Group 0 of the periodic table. Their atoms have very stable electronic structures

18. nucleus (of an atom)

q. the very small and dense central part of an atom that contains protons and neutrons

19. periodic table r. an arrangement of elements in the order of their atomic numbers, forming groups and periods

20. product s. a substance made as a result of a chemical reaction

21. proton t. a tiny positive particle found inside the nucleus of an atom

22. reactant u. a substance we start with before a chemical reaction takes place

23. shell v. an area in an atom, around its nucleus, where electrons are found

24. state symbol w. the abbreviations used in balanced symbol equations to show if reactants and products are solid (s), liquid (l), gas (g) or dissolved in water (aq)

25. symbol equation

x. an equation that helps you see how much of each substance is involved in a chemical reaction by showing the chemical symbols and formulae of all the reactants and products involved

y. 26. word equation z. a way of describing what happens in a chemical reaction by showing the names of all reactants and the products they form

Part 2: Key knowledge

1. Elements, compounds and chemical formulae

• All substances are made up of atoms.

• Atoms can be joined together by chemical bonds. If atoms of the same type are joined together, the

substance is called an element.

• The periodic table lists all the chemical elements, with eight main groups each containing elements

with similar chemical properties.

• If different types are joined together, the substance is called a compound. The names of the

elements can be found on the periodic table. Compounds are not found on the periodic table.

• The chemical formulae of a molecular substance tells you which atoms, and how many of them, are

present.

2. Chemical equations

• Chemical equations show the reactants (the substances your start with) and the products (the

substances made) in a reaction.

• Word and symbol equations can be used to represent chemical reactions.

• Symbol equations help you see ow much of each substance is involved in a reaction.

• The law of conservation of mass states: no new atoms are ever created or destroyed in a chemical

reaction (the total mass of reactants = the total mass of products)

• State symbols can be included in chemical equations to tell you more information:

(s) solids

(l) liquids

(aq) aqueous solutions

(g) gases

3. Separating mixtures

• A mixture is made up of two or more substances that are not chemically combined.

• Mixtures can be separated by physical techniques: filtration, crystallisation and

simple distillation.

a. Filtration

This technique is used to separate substances that are insoluble in a particular

solvent from those that are soluble in the solvent. E.g. sand and water

b. Crystallisation

This technique is used to crystallise a salt which is soluble in a solution (the

filtrate)

c. Distillation

This technique is used to collect a liquid from a mixture through evaporation and

condensation.

4. Fractional distillation

• A technique to separate miscible liquids based on the boiling points of liquids in the mixture

• This technique is used to separate ethanol from a fermented mixture in the alcoholic spirits

industry.

• Ethanol and water can be separated by this technique as they have different boiling points

(ethanol 78 °C)

5. Paper chromatography

• A technique to separate mixtures dissolved in a solvent e.g. ink

• Separation occurs in this process due to the difference in solubilities of the different

substances within the solvent.

6. History of the atom

• The ideas about atoms have changed overtime

• New evidence has been gathered from experiments of scientists who have used their model

of the atom to explain their observations and calculations

• Key individuals who propsed ideas about the atoms were Dalton, Thompson, Rutherford and

Bohr.

History of the Atom Summary Dalton’s model Atoms are tiny spheres that cannot be broken down. Plum pudding model (Thompson)

The atom is a ball of spread out positive charge with negative electrons studded into it

Nuclear model (Rutherford) An atom has a nucleus with a positive charge. Electrons orbit the nucleus. Between the nucleus and the electrons is empty space.

Electron shell model (Bohr) Electrons orbit the nucleus at a fixed energy level Protons and neutrons The nucleus consists of protons which have a positive charge and

neutrons which have no charge

7. Structure of the atom

• Atoms are made of three subatomic particles: protons, neutrons and electrons.

• Protons have a relative charge of +1 and electrons have a relative charge of -1. Neutrons have

no electric charge, they are neutral.

• Relative masses of a proton and neutron are both 1.

Subatomic particle Relative mass Relative charge

Proton 1 +1

Neutron 1 0

Electron 0 -1

On the periodic table, each element has two numbers:

Atomic number: the small number

This tells you the total number of protons in an atom

It also tells you the number of electrons. This is because an atom must have the same number of

positive charges and negative charges so it does not have an overall charge – the protons and electrons

cancel each other out.

Mass number: the big number

This tells you the total number of protons +neutrons in an atom

To work out number of neutrons: mass number – atomic number

8. Ions, atoms and isotopes

Ions • An ion is a charged particle produced by the loss or gain of electrons

• Atoms that gain electrons form negative ions

• Atoms that lost electrons form positive ions.

Isotopes • Atoms which have different atomic numbers are atoms of different elements.

• Atoms with the same atomic number but a different mass number are isotopes of the same

element.

• Isotopes have identical chemical properties, but their physical properties, such as density, can

differ.

Chlorine on the periodic table has a mass number of 35.5. With a mass number of 35.5 and its atomic

number is 17. How many neutrons does it have?

Number of neutrons = mass number – atomic number

Number of neutrons = 35.5 -17 = 18.5

This cannot be correct as you cannot have half a neutron. Instead, it represents the average mass of

all the atoms of chlorine in the universe.

Scientists have discovered that 75% of the atoms of chlorine in the universe have a mass of 35 (so 18

neutrons)

25% have a mass of 37 (so 20 neutrons)

The percentage is called the abundance

When we work out the mean mass we call it the relative atomic mass

(𝑎𝑏𝑢𝑛𝑑𝑎𝑛𝑐𝑒 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 1 × 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 1) + (𝑎𝑏𝑢𝑛𝑑𝑎𝑛𝑐𝑒 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 2 × 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 2)

100

So for chlorine:

Relative atomic mass = (75 ×35)+(25 ×37)

100= 35.5

Worked example – copper:

Copper has two isotopes. 69% is Cu-63 and 31% is Cu-65. What is the relative atomic mass?

We know that the equation for relative atomic mass is:

(𝑎𝑏𝑢𝑛𝑑𝑎𝑛𝑐𝑒 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 1 × 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 1) + (𝑎𝑏𝑢𝑛𝑑𝑎𝑛𝑐𝑒 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 2 × 𝑚𝑎𝑠𝑠 𝑜𝑓 𝑖𝑠𝑜𝑡𝑜𝑝𝑒 2)

100

Here, isotope 1 has an abundance of 69 and a mass of 63. Isotope 2 has an abundance of 31 and a

mass of 65. (69 × 63) + (31 × 65)

100= 63.62

9. Electronic structure • The number of electrons is the same as the atomic number of an atom

• Electrons orbit atoms in fixed energy levels (often called shells). • Two electrons can fit on the first shell. • 8 electrons can fit on the next shells. • The first shell needs to be filled before the second and the second before the third. • The number of electrons in the outermost shell of an element’s atoms determine the way in which

that element reacts.

Part 3: Key questions

Elements, compounds and chemical formulae

a. What is the smallest part of an element that can exist?

b. Define the term compound and give an example.

c. Complete the table below:

Name Formulae Element or compound?

Number of atoms?

Number of elements?

Oxygen

CaCl2

Sodium sulfate

Chemical equations

a. Define the term conservation of mass

b. What do state symbols tell you

c. Balance the equations below:

H2 + O2 H2O

CH4 + O2 CO2 + H2O

Na + Cl2 NaCl

Fe + O2 Fe2O3

Al + Br2 AlBr3

CaO + H2O Ca(OH)2

Separating mixtures

a. When mixtures are separated is this a physical or chemical process?

b. Complete the table below:

Substances to be separated

Name of separating technique

Description of how the technique works.

Sand and water

Salt and water

Water and ethanol

Mixture of food colourings

c. What is wrong with the setup of the equipment below to separate the solid yeast from the

solution?

d. Which property of substances in a mixture allows

distillation to work?

e. How many colours make up brown? How do you know?

Which colour is the most soluble?

The development of the Model of the Atom

a. Which model describes the atom as s a ball of positive charge with negative electrons

embedded in it?

b. Name the experiment which led scientists to believe the mass of an atom was mostly in the

centre.

c. What evidence led them to believe there was a positive nucleus?

d. What was the name of the model resulting from the experiment above?

e. How did Niels Bohr improve the nuclear model?

f. Which scientist provided evidence to show the nucleus contained neutrons as well as protons?

Structure of the atom

a. Complete the table to show the names of the 3 sub-atomic particles and their relative

charges and masses.

Sub-Atomic Particle Relative Mass Relative Charge 1

electron +1

b. In terms of sub-atomic particles, define the following terms:

atomic number

mass number

c. Where is the majority of mass found in an atom?

d. What is the approximate radius, in standard form, of:

an atom?

the nucleus of an atom?

Ions, atoms and isotopes

a. Define the term ion

b. Do metals form positive or negative ions? Why? c. Do non-metals form positive or negative ions? Why?

d. Complete the table to show the ion formed from each atom?

Atom Number of electrons in

outer shell Ion

Lithium

1 Li+

Cl-

Aluminium

Hydrogen

Bromine

Calcium

Oxygen

Barium

e. Define the term isotope and give an example.

f. Define the term relative atomic mass.

g. Explain why the relative atomic mass of chlorine is not a whole number.

h. Explain the difference between the two isotopes of carbon below in terms of their sub

atomic particles.

i. Calculate the relative atomic mass of the following elements

Element Isotopes Percentage Abudance

Relative atomic mass

Lithium

7.6%

92.4%

Magnesium

79%

10%

11%

Copper

70%

30%

Electronic structure

a. How many electrons can occupy the first energy level?

b. How many electrons can occupy the second energy level?

c. Name the element that has its electron configuration shown below.

d. On the diagram above, label the lowest and highest energy levels (shells). Which shell is

filled first?

e. How many electrons does an element in group 2 have in its highest occupied shell?

Li 6

3

Li 7

3

Mg 24

12

Mg 25

12

Mg 26

12

Cu 63

29

Cu 65

29

Chemistry

Quantitative chemistry

Part 1: Glossary

1. relative atomic mass Ar

the average mass of the atoms of an element compared with carbon-12 (which is given a mass of exactly 12). The average mass must take into account the proportions of the naturally occurring isotopes of the element

2. relative formula mass Mr

the total of the relative atomic masses, added up in the ratio shown in the chemical formula, of a substance

Part 2: Key knowledge

1. Chemical equations

• Chemical equations show the reactants (the substances your start with) and the products (the

substances made) in a reaction.

• Word and symbol equations can be used to represent chemical reactions.

• Symbol equations help you see ow much of each substance is involved in a reaction.

• The law of conservation of mass states: no new atoms are ever created or destroyed in a chemical

reaction (the total mass of reactants = the total mass of products)

• State symbols can be included in chemical equations to tell you more information:

(s) solids

(l) liquids

(aq) aqueous solutions

(g) gases

2. Change in masses

• In a chemical reaction the amount of products might appear to increase or decrease when gases are

involved.

• Mass of products appears to increase compared to the mass of reactants when a reactant is a gas

• Mass of products appears to decrease compared to the mass of reactants when a product is a gas as

gas from the reaction mixture of products might escape to the surrounding.

3. Calculating Mr • The Mr is the total of the relative atomic masses, added up in the ratio shown in the chemical

formula, of a substance.

• This can be calculated using a 4-step method:

Write out the elements

Write the number of atoms of each element

Calculate the Ar of the atoms of each element

Add up the total mass of the elements (this is your Mr!)

Part 3: Key questions

1. In a reaction, why does the mass of reactants always equal the mass of products?

2. In the equation: 2Li + F2 2LiF a) What does the 2 in front of LiF mean? b) What does the 2 mean in F2?

3. Explain why the following equation needs to be balanced:

2H2 + O2 2H2O

4. Calculate the relative formula mass of the following compounds: a) H2 b) H2O c) CaCl2 d) CO2

e) CaCO3

f) Ca(OH)2

5. In a reaction, the mass of the products must always equal the mass of the reactant. However, if a gas is

involved in can often look like the mass has gone up or down. a) Give an example of a reaction where it appears the mass of the product is greater than the reactant. b) Give an example of a reaction where it appears the mass of the reactant is greater than the product. c) A student heated 5g of calcium in an unsealed test tube so that it reacted with oxygen. At the end of the reaction, the mass of the product inside the test tube was 7g. Explain this observation.

Physics

Motion

Part 1: Glossary

1. acceleration change of velocity per second (in metres per second per second, m/s2)

2. deceleration change of velocity per second when an object slows down

3. displacement distance in a given direction

4. gradient (of a straight line graph)

change of the quantity plotted on the y-axis divided by the change of the quantity plotted on the x-axis

5. scalar a physical quantity which has magnititude only

6. tangent a straight line drawn to touch a point on a curve so it has the same gradient as the curve at that point

7. vector a physical quantity which has magnitude and direction

8. velocity speed in a given direction (in metres/second, m/s)

Part 2: Key knowledge

1. Speed and distance-time graphs

• The speed of an object is: v = s/t

• The distance-time graph for any object that is:

a. Stationary, is a horizontal line

b. Moving at costant speed, is a straight line that slopes upwards

c. The gradient of a distance-time graph for an object represents the objects speed

• The v=s/t equation can be rearranged to give s=vt or t=s/v

2. Velocity and acceleration

• Velocity is speed in a given direction

• A vector is a physical quantity that has a direction as well as a magnitude e.g. velocity.

• The accelaetation of an object is: a = change in velocity / time

• Deceleration is the change of velocity per second when an object slows down.

3. Velocity-time graphs

• A motion sensor linked to a computer can be used to measure velocity changes

• The gradient of a line on a velocity-time graph represents acceleration

• If a velocity-time graph is a horizontal link, the acceleration is zero.

• A positive gradeient on v-t graph represents positive acceleration, a negative gradient

represents deceleration.

• The area under a v-t grah represents distance travelled.

4. Analysing motion graphs

• The speed of an object moving at constant speed is given by the gradient of the line on its

distance-time graph

• The acceleration of an object is given by the gradient of the line of its velocity-time graph

• The distance travelled by an object is given by the area under the line on its v-t graph

• The speed at any instant time, of an object moving at a changing speed is given by the gradient

of the tangent to the line on its d-t graph.

Part 3: Key equations

Equation Triangle/manipulation Units Speed equation Speed = distance ÷ time

Speed = Distance = Time =

Speed in Distance in Time in

Acceleration equation 1 a = (v-u) t a= acceleration. v= final velocity u= initial velocity. t = time.

a= v= u= t =

Acceleration in Distance in Time in

Acceleration equation 2 v2= u2+2as v = final velocity u = initial velocity a = acceleration s = displacement

v = u = a = s =

Final velocity in Initial velocity in Acceleration in Displacement in

Part 4: Key questions

1. Speed and distance-time graphs

• State the equation, with units, that links speed, distance and

time.

• Match each of the distance-time graphs with the correct description

• A car travels 250m in 14 seconds. Calculate the speed of car with units.

• A train moves at a constant speed of 27m/s. Calculate the distance it travels in 120 seconds.

• A car moves at 30m/s for an hour. Calculate the distance it travels.

• Find the speed of the following:

a.

b.

c.

2. Velocity and acceleration

• State the equation, with units, that links acceleration, change in velocity and time.

• A sprinter in a 100m race accelerated from rest and reached a speed of 9.2m/s in the first 3.1s.

Calculate the acceleration of the sprinter.

• When a car joined the motorway, it accelerated from rest and reached a speed of 7.0 m/s for 10 s

at an acceleration of 2.0m/s2. Calculate its speed at the end of this time.

3. Velocity-time graphs

• State what each graph shows: acceleration, constant velocity, negative acceleration, or stationary:

1.

2.

3.

4.

4. Analysing motion graphs

• Find the acceleration of the objects in the following graphs

• Define acceleration.

• Write out the formula v2= u2+2as and state what each letter stands for.

• An object begins with an initial velocity of 12m/s and ends with a velocity of 63m/s. If the distance travelled is 125m, what is the acceleration?

• What distance is travelled by an object travelling first at 6m/s, accelerating at 4m/s2 to a final velocity 30m/s?

1.

2.

3.

4.