5.4 forces and motion - low demand - qs · page 1 of 47 5.4 forces and motion - low demand –...

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5.4 Forces and motion - Low demand – Questions

Q1. Figure 1 shows the forces acting on a car while it is moving.

Figure 1

(a) What is the resultant force acting on the car when it is travelling at constant velocity?

Resultant force = ____________________ N (1)

(b) The car accelerates at 0.8 m/s2

The mass of the car is 850 kg

Calculate the resultant force acting on the car while it is accelerating.

Use the equation:

resultant force = mass × acceleration

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________


(c) The driver notices a hazard and applies the brakes.

The car is travelling at 12 m/s

The driver’s reaction time is 0.180 s

Calculate the distance travelled during the driver’s reaction time.

Use the equation:

distance travelled = speed × time

___________________________________________________________________

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___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

Distance travelled = ____________________ m (2)

(d) Figure 2 shows how the thinking distance, braking distance and stopping distance of a car change with speed.

Figure 2

Describe the trends in the data in Figure 2.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________ (3)

(Total 8 marks)

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Q2. Figure 1 shows the forces acting on a car moving at a constant speed.

Figure 1

(a) Which force would have to increase to make the car accelerate?

Tick one box.

A

B

C

D

(1)

(b) The car travels a distance of 2040 metres in 2 minutes.

Use the following equation to calculate the mean speed of the car.

___________________________________________________________________

___________________________________________________________________

Mean speed = __________________ m / s (2)

(c) The car makes an emergency stop.

Figure 2 shows the thinking distance and braking distance of the car.

Figure 2

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What is the stopping distance?

___________________________________________________________________ (1)

(d) The person driving the car is tired.

What effect will this have on the thinking distance and braking distance?

Tick one box for thinking distance.

Tick one box for braking distance.

decreases increases stays the same

thinking distance

braking distance

(2) (Total 6 marks)

Q3. A number of different forces act on a moving vehicle.

(a) A car moving at a steady speed has a driving force of 3000 N.

(i) What is the value of the resistive force acting on the car?

Tick ( ) one box.

Tick ( )

2000 N

3000 N

4000 N

(1)

(ii) What causes most of the resistive force?

Tick ( ) one box.

Tick ( )

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Air resistance

Faulty brakes

Poor condition of tyres

(1)

(b) A car is moving along a road. The driver sees an obstacle in the road at time t = 0 and applies the brakes until the car stops.

The graph shows how the velocity of the car changes with time.

(i) Which feature of the graph represents the negative acceleration of the car?

Tick ( ) one box.

Tick ( )

The area under the graph

The gradient of the sloping line

The intercept on the y-axis

(1)

(ii) Which feature of the graph represents the distance travelled by the car?

Tick ( ) one box.

Tick ( )

The area under the graph

The gradient of the sloping line

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The intercept on the y-axis

(1)

(iii) On a different journey, the car is moving at a greater steady speed.

The driver sees an obstacle in the road at time t = 0 and applies the brakes until the car stops.

The driver’s reaction time and the braking distance are the same as shown the graph above.

On the graph above draw another graph to show the motion of the car. (3)

(c) In this question you will be assessed on using good English, organising information clearly and using specialist terms where appropriate.

Thinking distance and braking distance affect stopping distance.

Explain how the factors that affect thinking distance and braking distance affect stopping distance.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________ (6)

(Total 13 marks)

Q4. A small object falls out of a balloon.

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Choose words from the list to complete the sentences below.

friction gravity air pressure

accelerates falls at a steady speed slows down

• The weight of an object is the force of ______________________ which acts on it.

• When you drop something, first of all it ________________________ .

• The faster it falls, the bigger the force of _____________________ which acts on it.

• Eventually the object _______________________ . (Total 4 marks)

Q5. The graph shows the distance a person walked on a short journey.

(a) Choose from the phrases listed to complete the statements which follow. You may use each statement once, more than once or not at all.

standing still

walking at constant speed

walking with an increasing speed

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walking with a decreasing speed

(i) Between points A and B the person is

______________________________________________________________ (1)

(ii) Between points B and C the person is

______________________________________________________________ (1)

(b) Complete the sentence.

You can tell that the speed of the person between points A and B is ____________

than the speed between points C and D because ___________________________

___________________________________________________________________ (2)

(c) Write the equation which relates distance, speed and time.

___________________________________________________________________ (1)

(Total 5 marks)

Q6.

(a) A driver may have to make an emergency stop.

Stopping distance = thinking distance + braking distance.

Give three different factors which affect the thinking distance or the braking distance. In your answer you should explain what effect each factor has on the stopping distance.

1. _________________________________________________________________

___________________________________________________________________

___________________________________________________________________

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___________________________________________________________________

2. _________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

3. _________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________ (6)

(b) Complete the following sentences by writing in the two missing words.

Acceleration is the rate of change of _______________________________ .

The acceleration of a car depends on the force applied by the engine and the

______________________ of the car. (2)

(c) A car moves because of the force applied by the engine.

Name two other forces which act on the car when it is moving. Give the direction in which each of these factors acts.

1. _________________________________________________________________

Direction of this force _________________________________________________

2. _________________________________________________________________

Direction of this force _________________________________________________ (4)

(d) Complete the following sentence by writing in the missing word.

The velocity of a car is its speed in a particular _________________________ (1)

(Total 13 marks)

Q7. (a) The model bus is being pushed on a table.

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(i) At first the pushing force does not make the model bus move. Explain why.

______________________________________________________________

______________________________________________________________ (1)

(ii) Write down two things that happen as the pushing force increases.

1. ____________________________________________________________

______________________________________________________________

2. ____________________________________________________________

______________________________________________________________ (2)

(iii) Complete the formula by choosing the correct words from the box.

acceleration distance moved force applied

speed time taken

Work done on the model bus = ________________ × ________________

(2)

(b) In this situation, the car driver needs to stop the car in the shortest possible distance.

(i) Complete the table by putting ticks ( ) to show which factors would make the

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stopping distance greater. The first one has been done for you.

Factor Tick ( ) makes stopping distance greater

brakes are old and worn

car is travelling fast

driver has been drinking alcohol

four new tyres are fitted

hot, dry, sunny weather

ice on the road

(3)

(ii) Complete the sentence by writing the correct words in the spaces.

The car will skid if the braking force is too big compared with the friction

between the car’s __________________ and the __________________ . (1)

(Total 9 marks)

Q8. This question is about a car travelling through a town.

(a) The graph shows how far the car travelled and how long it took.

(i) Between which points was the car travelling fastest? Tick ( ) your answer.

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Points Tick ( )

A – B

B – C

C – D

D – E

E – F

(1)

(ii) Between which points was the car stationary?

______________________________________________________________

______________________________________________________________ (1)

(b) Complete the sentences by writing the correct words in the spaces.

When a car has to stop, the overall stopping distance is greater if:

• the car is poorly maintained;

• there are adverse weather conditions;

• the car is travelling ________________ ;

• the driver’s reactions are ________________ .

Also, the greater the speed of the car, then the greater the braking _____________

needed to stop in a certain time. (3)

(Total 5 marks)

Q9. The diagram below shows the thinking distances, braking distances and total stopping distances at different speeds.

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(a) Look at the total stopping distances at each speed.

Complete the sentence by choosing the correct words from the box.

distance force mass time

The total stopping distance depends on the distance the car travels during the

driver’s reaction _______________ and under the braking ________________ . (2)

(b) Give three other factors that could cause the total stopping distance of a car to be greater. Do not give the factors in Figure 1.

1. _________________________________________________________________

___________________________________________________________________

2. _________________________________________________________________

___________________________________________________________________

3. _________________________________________________________________

___________________________________________________________________ (3)

(Total 5 marks)

Q10. (a) A shopping trolley is being pushed at a constant speed. The arrows represent the

horizontal forces on the trolley.

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(i) How big is force P compared to force F?

______________________________________________________________ (1)

(ii) Which one of the distance-time graphs, K, L or M, shows the motion of the trolley? Draw a circle around your answer.

(1)

(b) Complete the sentence by crossing out the two words in the box that are wrong.

Acceleration is the rate of change of (1)

(c) Three trolleys, A, B and C, are pushed using the same size force. The force causes each trolley to accelerate.

Which trolley will have the smallest acceleration?

___________________________________________________________________

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Give a reason for your answer.

___________________________________________________________________ (2)

(Total 5 marks)

Q11. (a) Two skydivers jump from a plane. Each holds a different position in the air.

A B

Adapted from Progress with Physics by Nick England, reproduced by permission of Hodder Arnold

Complete the following sentence.

Skydiver ____________ will fall faster because_____________________________

___________________________________________________________________

___________________________________________________________________ (2)

The diagram shows the direction of the forces acting on one of the skydivers.

Adapted from Progress with Physics by Nick England, reproduced by permission of Hodder Arnold

(b) In the following sentences, cross out in each box the two lines that are wrong.

(i) Force X is caused by (1)

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(ii) Force Y is caused by (1)

(iii) When force X is bigger than force Y, the speed of the

skydiver will (1)

(iv) After the parachute opens, force X (1)

(c) How does the area of an opened parachute affect the size of force Y?

___________________________________________________________________

___________________________________________________________________ (1)

(Total 7 marks)

Q12. A horse and rider take part in a long distance race. The graph shows how far the horse and rider travel during the race.

(a) What was the distance of the race?

distance = _________________________________ km (1)

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(b) How long did it take the horse and rider to complete the race?

___________________________________________________________________ (1)

(c) What distance did the horse and rider travel in the first 2 hours of the race?

distance = _________________________________ km (1)

(d) How long did the horse and rider stop and rest during the race?

___________________________________________________________________ (1)

(e) Not counting the time it was resting, between which two points was the horse moving the slowest?

_________________ and _________________


___________________________________________________________________

___________________________________________________________________ (2)

(Total 6 marks)

Q13. The diagram shows a sky-diver in free fall. Two forces, X and Y, act on the sky-diver.

(a) Complete these sentences by crossing out the two lines in each box that are wrong.

(i) Force X is caused by . (1)

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(ii) Force Y is caused by . (1)

(b) The size of force X changes as the sky-diver falls. Describe the motion of the sky-diver when:

(i) force X is smaller than force Y,

______________________________________________________________

______________________________________________________________ (2)

(ii) force X is equal to force Y.

______________________________________________________________

______________________________________________________________ (1)

(Total 5 marks)

Q14. A car and a bicycle are travelling along a straight road. They have stopped at road works.

The graph shows how the velocity of the car changes after the sign is changed to GO.

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(a) Between which two points on the graph is the car moving at constant velocity?

___________________________________________________________________ (1)

(b) Between which two points on the graph is the car accelerating?

___________________________________________________________________ (1)

(c) Between the sign changing to GO and the car starting to move, there is a time delay. This is called the reaction time.

(i) What is the reaction time of the car driver?

Reaction time = _________________ seconds (1)

(ii) Which one of the following could increase the reaction time of a car driver? Tick the box next to your choice.

Drinking alcohol

Wet roads

Worn car brakes (1)

(d) The cyclist starts to move at the same time as the car. For the first 2 seconds the cyclist’s acceleration is constant and is greater than that of the car.

Draw a line on the graph to show how the velocity of the cyclist might change during the first 2 seconds of its motion.

(2) (Total 6 marks)

Q15. The diagram shows the forces on a small, radio-controlled, flying toy.

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(a) (i) The mass of the toy is 0.06 kg. Gravitational field strength = 10 N/kg

Calculate the weight of the toy.

Show clearly how you work out your answer and give the unit.

______________________________________________________________

______________________________________________________________

Weight = _________________________ (3)

(ii) Complete the following sentence by drawing a ring around the correct line in the box.

When the toy is hovering stationary in mid-air, the lift force is

bigger than

the same as

smaller than

the weight of the toy.

(1)

(b) When the motor inside the toy is switched off, the toy starts to accelerate downwards.

(i) What does the word accelerate mean?

______________________________________________________________ (1)

(ii) What is the direction of the resultant force on the falling toy?

______________________________________________________________ (1)

(Total 6 marks)

Q16. (a) A car driver makes an emergency stop.

The chart shows the ‘thinking distance’ and the ‘braking distance’ needed to stop the car.

Calculate the total stopping distance of the car.

___________________________________________________________________

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Stopping distance = _________________________ m (1)

(b) The graph shows how the braking distance of a car driven on a dry road changes with the car’s speed.

The braking distance of the car on an icy road is longer than the braking distance of the car on a dry road.

(i) Draw a new line on the graph to show how the braking distance of the car on an icy road changes with speed.

(2)

(ii) Which two of the following would also increase the braking distance of the car?

Put a tick ( ) next to each of your answers.

rain on the road

the driver having drunk alcohol

car brakes in bad condition

the driver having taken drugs

(2)

(c) The thinking distance depends on the driver’s reaction time.

The table shows the reaction times of three people driving under different conditions.

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Car driver Condition Reaction time in seconds

A Wide awake with no distractions 0.7

B Using a hands-free mobile phone 0.9

C Very tired and listening to music 1.2

The graph lines show how the thinking distance for the three drivers, A, B and C, depends on how fast they are driving the car.

(i) Match each graph line to the correct driver by writing A, B or C in the box next to the correct line.

(2)

(ii) The information in the table cannot be used to tell if driver C’s reaction time is increased by being tired or by listening to music.

Explain why.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (2)

(Total 9 marks)

Q17. The diagram shows the horizontal forces acting on a car travelling along a straight road.

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(a) Complete the following sentences by drawing a ring around the correct word in each box.

(i) When the driving force equals the drag force, the speed ofthe car is

decreasing

constant

increasing

(1)

(ii) Putting the brakes on transforms the car’s kinetic energy mainly into

heat

light

sound

(1)

(b) The charts, A, B and C give the thinking distance and the braking distance for a car driven under different conditions.

(i) Draw straight lines to match each chart to the correct conditions.

Draw only three lines.

(2)

(ii) The three charts above all apply to dry road conditions.

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How would the braking distances be different if the road were wet?

______________________________________________________________

______________________________________________________________ (1)

(Total 5 marks)

Q18. Part of a bus route is along a high street. The distance – time graph shows how far the bus travelled along the high street and how long it took.

(a) The bus travels the slowest between points D and E.

How can you tell this from the graph?

___________________________________________________________________

___________________________________________________________________ (1)

(b) Between which two points was the bus travelling the fastest?

Put a tick ( ) in the box next to your answer.

Points

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A – B

B – C

C – D

(1)

(c) There is a bus stop in the high street. This is marked as point B on the graph.

(i) What is the distance between point A on the graph and the bus stop?

Distance _______________ metres (1)

(ii) How long did the bus stop at the bus stop? Show clearly how you work out your answer.

______________________________________________________________

Time = _______________ seconds (2)

(d) A cyclist made the same journey along the high street. The cyclist started at the same time as the bus and completed the journey in 200 seconds. The cyclist travelled the whole distance at a constant speed.

(i) Draw a line on the graph to show the cyclist’s journey. (2)

(ii) After how many seconds did the cyclist overtake the bus?

The cyclist overtook the bus after _______________ seconds. (1)

(Total 8 marks)

Q19. (a) The total stopping distance of a car has two parts. One part is the distance the car

travels during the driver’s reaction time. This distance is often called the ‘thinking distance’.

What distance is added to the ‘thinking distance’ to give the total stopping distance?

___________________________________________________________________

___________________________________________________________________ (1)

(b) The graph shows the relationship between the speed of a car and the thinking distance.

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Describe the relationship between speed and thinking distance.

___________________________________________________________________

___________________________________________________________________ (2)

(c) The diagram shows two students investigating reaction time.

One student holds a 30 cm ruler, then lets go. As soon as the second student sees the ruler fall, she closes her hand, stopping the ruler. The further the ruler falls before being stopped, the slower her reaction time.

(i) One student always holds the ruler the same distance above the other

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student’s hand. In this experiment, what type of variable is this?


independent variable

dependent variable

control variable

(1)

(ii) Describe how this experiment could be used to find out whether listening to music affects reaction time.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (2)

(d) The following information is written on the label of some cough medicine.

WARNING: Causes drowsiness. Do not drive or operate machinery.

How is feeling drowsy (sleepy) likely to affect a driver’s reaction time?

___________________________________________________________________

___________________________________________________________________ (1)

(e) Three cars, X, Y and Z , are being driven along a straight road towards a set of traffic lights. The graphs show how the velocity of each car changes once the driver sees that the traffic light has turned to red.

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Which one of the cars, X, Y or Z , stops in the shortest distance?

___________________ (1)

(Total 8 marks)

Q20. Motorway accidents have many causes.

(a) Which one of the following is most likely to increase the chance of a car being in an accident?

Tick ( ) the box next to your answer.

The car has just had new tyres fitted.

The driver has been drinking alcohol.

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A road surface in dry conditions


___________________________________________________________________

___________________________________________________________________ (2)

(b) The diagram shows three designs of motorway crash barriers.

Steel sheets Steel ‘ropes’ Solid concrete

Before a new design of barrier is used, it must be tested. A car of mass 1500 kg is driven at 30 m/s to hit the barrier at an angle of 20 degrees. This barrier must slow the car down and must not break.

Explain why the mass of the car, the speed of the car and the angle at which the car hits the barrier must be the same in every test.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________ (2)

(c) A group of scientists has suggested that new designs of crash barriers should be first tested using computer simulations.

Which two statements give sensible reasons for testing new barrier designs using a computer simulation?

Put a tick ( ) in the box next to each of your answers.

The design of the barrier can be changed easily.

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Data for different conditions can be obtained quickly.

Simulations are more realistic than using cars and barriers.

(1) (Total 5 marks)

Q21. A high-speed train accelerates at a constant rate in a straight line.

The velocity of the train increases from 30 m/s to 42 m/s in 60 seconds.

(a) (i) Calculate the change in the velocity of the train.

______________________________________________________________

Change in velocity = _______________ m/s (1)

(ii) Use the equation in the box to calculate the acceleration of the train.

Show clearly how you work out your answer and give the unit. Choose the unit from the list below.

m/s m/s2 N/kg Nm

______________________________________________________________

______________________________________________________________

Acceleration = _________________________ (2)

(b) Which one of the graphs, A, B or C, shows how the velocity of the train changes as it accelerates?

Write your answer, A, B or C, in the box.

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A

B

C

Graph (1)

(Total 4 marks)

Q22. (a) The diagrams, A, B and C, show the horizontal forces acting on a moving car.

Draw a line to link each diagram to the description of the car's motion at the moment when the forces act.

Draw only three lines.

stationary

A

constant speed

B

slowing down

C

accelerating forwards

(3)

(b) The front crumple zone of a car is tested at a road traffic laboratory. This is done by using a remote control device to drive the car into a strong barrier. Electronic sensors are attached to a dummy inside the car.

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(i) Draw an arrow in Box 1 to show the direction of the force that the car exerts on the barrier.

(1)

(ii) Draw an arrow in Box 2 to show the direction of the force that the barrier exerts on the car.

(1)

(iii) Complete the following by drawing a ring around the correct line in the box.

The car exerts a force of 5000 N on the barrier. The barrier does not move.

more than

The force exerted by the barrier on the car will be equal to 5000 N.

less than

(1)

(iv) Which one of the following gives the most likely reason for attaching electronic sensors to the dummy?


To measure the speed of the car just before the impact.

To measure the forces exerted on the dummy during the impact.

To measure the distance the car travels during the impact. (1)

(Total 7 marks)

Q23. (a) A car driver makes an emergency stop.

The chart shows the ‘thinking distance’ and the ‘braking distance’ needed to stop the car.

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Calculate the total stopping distance of the car.

___________________________________________________________________

Stopping distance = _________________________ m (1)

(b) The graph shows how the braking distance of a car driven on a dry road changes with the car’s speed.

Speed in m/s

The braking distance of the car on an icy road is longer than the braking distance of the car on a dry road.

(i) Draw a new line on the graph to show how the braking distance of the car on an icy road changes with speed.

(2)

(ii) Which one of the following would also increase the braking distance of the car?


Rain on the road

The driver having drunk alcohol

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The driver having taken drugs

(1)

(c) The thinking distance depends on the driver’s reaction time.

The table shows the reaction times of three people driving under different conditions.

Car driver Condition

Reaction time in second

A Wide awake with no distractions 0.7

B Using a hands-free mobile phone 0.9

C Very tired and listening to music 1.2

The graph lines show how the thinking distance for the three drivers, A, B, and C, depends on how fast they are driving the car.

Speed in m/s

(i) Match each graph line to the correct driver by writing A, B, or C in the box next to the correct line.

(2)

(ii) The information in the table cannot be used to tell if driver C’s reaction time is increased by being tired or by listening to music. Explain why.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

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(2) (Total 8 marks)

Q24. (a) The diagram shows two forces acting on an object.

What is the resultant force acting on the object?

Tick ( ) one box.

8 N to the right

8 N to the left

4 N to the right

4 N to the left

(1)

(b) BASE jumpers jump from very high buildings and mountains for sport.

The diagram shows the forces acting on a BASE jumper in flight. The BASE jumper is wearing a wingsuit.

(i) Draw a ring around the correct answer in the box to complete each sentence.

The BASE jumper accelerates forwards when force A

smaller than

is equal to force B.

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bigger than

The BASE jumper falls with a constant speed when force C

smaller than

is equal to force D.

bigger than

(2)

(ii) To land safely the BASE jumper opens a parachute.

What effect does opening the parachute have on the speed of the falling BASE jumper?

______________________________________________________________


______________________________________________________________

______________________________________________________________ (2)

(Total 5 marks)

Q25. The diagram shows how the thinking distance and braking distance of a car add together to give the stopping distance of the car.

(a) Use words from the box to complete the sentence.

distance energy force time

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The stopping distance is found by adding the distance the car travels during the

driver’s reaction ____________________ and the distance the car travels under the

braking ____________________ . (2)

(b) Which one of the following would not increase the thinking distance?

Tick ( ) one box.

The car driver being tired.

The car tyres being badly worn.

The car being driven faster.

(1)

(c) The graph shows how the braking distance of a car changes with the speed of the car. The force applied to the car brakes does not change.

Speed in metres/second

(i) What conclusion about braking distance can be made from the graph?

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

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(2)

(ii) The graph is for a car driven on a dry road.

Draw a line on the graph to show what is likely to happen to the braking distance at different speeds if the same car was driven on an icy road.

(1)

(d) A local council has reduced the speed limit from 30 miles per hour to 20 miles per hour on a few roads. The reason for reducing the speed limit was to reduce the number of accidents.

(i) A local newspaper reported that a councillor said:

“It will be much safer because drivers can react much faster when driving at 20 miles per hour than when driving at 30 miles per hour.”

This statement is wrong. Why?

______________________________________________________________

______________________________________________________________ (1)

(ii) The local council must decide whether to introduce the lower speed limit on a lot more roads.

What evidence should the local council collect to help make this decision?

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (2)

(Total 9 marks)

Q26. (a) Figure 1 shows the distance–time graph for a person walking to a bus stop.

Figure 1

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Time in seconds

(i) Which one of the following statements describes the motion of the person between points R and S on the graph?

Tick (✓) one box.

Not moving

Moving at constant speed

Moving with increasing speed

(1)

(ii) Another person, walking at constant speed, travels the same distance to the bus stop in 200 seconds.

Complete Figure 2 to show a distance–time graph for this person.

Figure 2

Time in seconds

(1)

(b) A bus accelerates away from the bus stop at 2.5 m/s2.

The total mass of the bus and passengers is 14 000 kg.

Calculate the resultant force needed to accelerate the bus and passengers.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________


(Total 4 marks)

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Q27. On 14 October 2012, a skydiver set a world record for the highest free fall from an aircraft.

After falling from the aircraft, he reached a maximum steady velocity of 373 m / s after 632 seconds.

(a) Draw a ring around the correct answer to complete the sentence.

This maximum steady velocity is called the

frictional

initial

terminal

velocity.

(1)

(b) The skydiver wore a chest pack containing monitoring and tracking equipment. The weight of the chest pack was 54 N.

The gravitational field strength is 10 N / kg.

Calculate the mass of the chest pack.

___________________________________________________________________

___________________________________________________________________

Mass of chest pack = ____________________ kg (2)

(c) During his fall, the skydiver’s acceleration was not uniform.

Immediately after leaving the aircraft, the skydiver’s acceleration was 10 m / s2.

(i) Without any calculation, estimate his acceleration a few seconds after leaving the aircraft.

Explain your value of acceleration in terms of forces.

Estimate ______________________________________________________

Explanation ____________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (3)

(ii) Without any calculation, estimate his acceleration 632 seconds after leaving the aircraft.

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Explain your value of acceleration in terms of forces.

Estimate ______________________________________________________

Explanation ____________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (3)

(Total 9 marks)

Q28. (a) When a force is applied to a spring, the spring extends by 0.12 m.

The spring has a spring constant of 25 N/m.

Calculate the force applied to the spring.

___________________________________________________________________

___________________________________________________________________

Force = ________________________ N (2)

(b) Figure 1 shows a toy glider. To launch the glider into the air, the rubber band and glider are pulled back and then the glider is released.

(i) Use the correct answers from the box to complete the sentence.

chemical elastic potential kinetic thermal

When the glider is released, the _________________________ energy

stored in the rubber band decreases and the glider gains

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_________________________ energy. (2)

(ii) Figure 2 shows how the extension of the rubber band varies with the force applied to the rubber band.

What can you conclude, from Figure 2, would happen to the extension of the rubber band if the force applied to the rubber band was increased to 6 N?

The rubber band does not break.

______________________________________________________________

______________________________________________________________

______________________________________________________________

______________________________________________________________ (2)

(c) Figure 3 shows the vertical forces, A and B, acting on the glider when it is flying.

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(i) What name is given to the force labelled B?

Draw a ring around the correct answer.

drag friction weight

(1)

(ii) Which one of the following describes the downward speed of the glider when force B is greater than force A?

Tick ( ) one box.

Downward speed increases

Downward speed is constant

Downward speed decreases

(1) (Total 8 marks)

Q29. Speed and velocity are different quantities.

(a) Complete the sentence.

Choose the answers from the box.

distance direction scalar time vector

Velocity is a ____________________________ quantity.

The velocity of an object is its speed in a given ____________________________ . (2)

Figure 1 shows the distance-time graph for an athlete in a running race.

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Figure 1

(b) Determine the:

• distance of the race

• time taken for the athlete to complete the race.

Use Figure 1.

___________________________________________________________________

Distance = ____________________ km

Time taken = ____________________ minutes (2)

(c) What is the motion of the athlete between points B and C on Figure 1?

Tick one box.

Moving at constant speed

Moving with decreasing speed

Moving with increasing speed

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Not moving

(1)

(d) Which section on Figure 1 shows the athlete moving at the highest speed?

Tick one box.

A to B

B to C

C to D

D to E

(1)

(e) How does the section you gave as your answer in part (d) show the highest speed?

___________________________________________________________________

___________________________________________________________________ (1)

(f) A cyclist travelled the same distance as the athlete.

The cyclist travelled at a constant speed for 120 minutes.

Complete Figure 2 to show a distance-time graph for the cyclist.

Figure 2

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(2)

A car following the race accelerates at a constant rate in a straight line.

The velocity of the car increases from 1.9 m/s to 3.4 m/s in 60 seconds.

(g) Calculate the change in velocity of the car.

___________________________________________________________________

Change in velocity = ____________________ m/s (1)

(h) Calculate the acceleration of the car.

Use your answer to part (g).

Use the equation:

Give the unit.

___________________________________________________________________

___________________________________________________________________

___________________________________________________________________

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Acceleration = ____________________ unit ____________________ (3)

(i) Which graph shows how the velocity of the car changes as the car accelerates?

Tick one box.

(1)

(Total 14 marks)

5.4 forces and motion - low demand - qs · page 1 of 47 5.4 forces and motion - low demand –...

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