Edexcel GCSE Physics

Topic Questions

2.3 Momentum

1a
Sme Calculator
1 mark

Which are the correct units for momentum?

square   A   kg m s

square   B   J

square   C   N m

square   D   kg m/s

1b
Sme Calculator
1 mark

State the equation used to define momentum.

1c
Sme Calculator
2 marks

State the law of conservation of momentum. 

Did this page help you?

2a
Sme Calculator
2 marks

Which equations relating, momentum (p), mass (m) and velocity (v) are correct?

Tick (✓) two boxes.

p space equals space m over v begin mathsize 36px style square end style
v space equals space p over m square
m space equals space p v square
v space equals space m over p square
p space equals space m v square
m space equals space v over p square
2b
Sme Calculator
1 mark

State the condition necessary for total momentum before to be equal to total momentum after an event.

2c
Sme Calculator
4 marks

Complete the sentences. 

Choose answers from the box. 

Each answer can be used once, more than once or not at all.

  

elastic different inelastic identical

  

When a collision is .............................. the objects move in opposite directions.

The velocities of the objects are ..............................

      

When a collision is .............................. the objects move in the same direction together.

The velocities of the objects are ..............................

2d
Sme Calculator
4 marks

Tony falls off his skateboard, sending it flying forward at 8.5 m/s.

The skateboard has a mass of 1.5 kg.

Calculate the momentum of the skateboard.

Give your answer to 2 significant figures and give the units.

  

  

momentum (2 significant figures) = .................................... units = .........................

Did this page help you?

3a
Sme Calculator
2 marks

A stationary leaky oil barrel is left unattended overnight next to a stationary faulty radio, shown in Figure 1.

5-9-e-2a-oil-barrel-and-radio

Figure 1

A spark from the radio ignites the oil leak, causing an explosion between the two objects.

State the initial momentum of the system, before the explosion.

Explain how you arrived at your answer.

You may assume the system is closed.

3b
Sme Calculator
2 marks

State the total momentum of the system after the explosion.

Name the physics law you used to determine this answer.

3c
Sme Calculator
3 marks

Right is defined as the positive direction. 

The oil barrel has a mass of 80 kg and moves to the left with a velocity of −3.0 m/s.

Calculate the momentum of the oil barrel.

  

  

momentum = .................................... kg m/s

3d
Sme Calculator
1 mark

State the momentum of the radio after the collision.

Did this page help you?

1a3 marks

Higher Only

 

Figure 1 is a diagram showing a rocket that is sent into space to try and change the path of a small asteroid.

fig-12-paper1h-june2020-edexcel-gcse-physics

Figure 12

i)
The rocket has a mass of 5.5 × 105 kg and is travelling to the right at 14 km/s.

Which of these is a correct calculation of the momentum of the rocket in kg m/s?

  A 7.7 × 103 kg m/s
  B 7.7 × 106 kg m/s
  C 7.7 × 109 kg m/s
  D 7.7 × 1012 kg m/s

[1]

ii)
The asteroid has a momentum of 7.5 × 1010 kg m/s and a mass of 8.0 × 106 kg.
Calculate the speed of the asteroid.

 [2]


speed of the asteroid = .............................................................. m/s

1b6 marks

Higher Only

 

A student investigates the effect of a crumple zone on the force exerted during a collision.

The student has one trolley with a spring at the front and another trolley without a spring.

fig-13-paper1h-june2020-edexcel-gcse-physics

Figure 13

After a trolley is released, it accelerates down a slope and bounces off a rigid wall.
The speed of a trolley can be measured just before a collision with the wall and just after a collision with the wall.
The silver foils are connected to a millisecond timer.
The silver foils make contact with each other during the collision, so the time they are in contact can be read from the millisecond timer.

Explain how the student could investigate the effect of a crumple zone on the average force exerted during the collision.
Your explanation should include:

  • how to determine the force (you may wish to refer to an equation from the list of equations at the end of this paper)
  • how the effect of crumple zones may be shown in the investigation
  • precautions that may be necessary to achieve accurate results
1c4 marks

Higher Only 

 

Newton’s third law, when applied to the collision of the rocket and the asteroid as shown in Figure 12, can be stated as follows:

The force exerted by the rocket on the asteroid is equal and opposite to the force exerted by the asteroid on the rocket.

Explain how this statement links to the conservation of momentum in the collision.

Did this page help you?

2a
Sme Calculator
4 marks

Higher Only

Car A has a mass of 600 kg and is travelling at at 30 miles per hour (miles/hour) to the right.

Car B is behind car A and is travelling at 40 miles/hour to the right.

The total momentum of the system is 58 000 kg miles/hour.

Calculate the mass of car B in kg.

Give your answer to 2 significant figures.

2b
Sme Calculator
4 marks

Higher Only

The driver of car B is on their phone and they crash into the back of car A.

After the collision, both cars stick together and travel forward at the same speed. 

Calculate the combined speed of the cars, giving the unit. 

Give your answer to 2 significant figures.

2c
Sme Calculator
5 marks

Higher Only

Show that kinetic energy is not conserved in this collision.

2d3 marks

Higher Only

The collision occurs in 0.55 s.

Calculate the force experienced by car A to the appropriate number of significant figures.

Did this page help you?

3a
Sme Calculator
3 marks

Higher Only

Modern cars all feature crumple zones, which are designed to buckle and break in the event of a crash, as shown in Figure 1.

image

Figure 1

  

Derive the equation F space equals space fraction numerator straight capital delta p over denominator t end fraction from the equations a space equals space fraction numerator straight capital delta v over denominator t end fraction comma space p space equals space m v and F space equals space m a, where F is force, straight capital delta p is change in momentum, t is time, a is acceleration, straight capital delta v is change in velocity and m is mass.

3b
Sme Calculator
2 marks

Higher Only

Using the equation relating force and momentum given in part (a), explain how the crumple zone of the car reduces the risk of injury in a crash.

3c
Sme Calculator
3 marks

Higher Only

Using the equation relating force and momentum given in part (a), explain why driving at a lower velocity is generally safer. 

3d
Sme Calculator
4 marks

Higher Only

State whether it is safer for the passenger to crash into a wall or a parked vehicle. Explain your answer.

Did this page help you?

1a2 marks

Higher Only

Figure 10 shows a small steel ball held at a height, h, above the ground.

LRUFAlz~_fig-10-paper1h-oct2021-edexcel-gcse-physics
Figure 10


The ball is released and allowed to fall to the ground.

The height h is 1.4 m.

Calculate the time, t, for the ball to reach the ground.

Use the equation

t squared equals fraction numerator 2 h over denominator g end fraction

g = 10 m/s2

t = ............................................................. s

1b2 marks

Higher Only

Two students use the arrangement shown in Figure 10.

They use a stopwatch to time the ball falling through the height of 1.4 m.

The students repeat the measurement many times, but their average value for t is different from the calculated value.

i)
Suggest a reason why the students’ value for t is different from the calculated value.

[1]

ii)
Suggest one improvement the students could make to their procedure so that their value for t is closer to the calculated value.

[1]

1c4 marks

Higher Only

Figure 11a shows a box falling towards a hard floor.

fig-11a-11b-paper1h-oct2021-edexcel-gcse-physics


The box hits the floor and crumples a little before it comes to rest as shown in Figure 11b.

The momentum of the box just before it hits the floor is 8.7 kg m/s.

The box comes to rest 0.35 s after it first hits the floor.

i)
Calculate the magnitude of the force exerted by the floor on the box.

Use an equation selected from the list of equations at the end of this paper.

[2]

force exerted by the floor on the box =................................. N

ii)
State the magnitude and direction of the force exerted by the box on the floor.

[2]
magnitude .....................................
direction .....................................
1d4 marks

Higher Only

 

Figure 12 shows a ball held in a clamp at R, above the ground.

fig-12-paper1h-oct2021-edexcel-gcse-physics

Figure 12


The ball is released from the clamp and falls.

S is 3.8 m below R.

At S the momentum of the ball is 0.40 kg m/s.

Calculate the mass of the ball.

Acceleration due to gravity, g, = 10 m/s2

mass of the ball ............................................................. kg

Did this page help you?

2a2 marks

Higher Only

Complete Figure 1 by writing in the right-hand column the name of the quantity produced by the expression in the left-hand column.
  
Expression Quantity
change in momentum ÷ time  
mass × velocity  

  Figure 1

2b4 marks

Higher Only

In Figure 2, a man hits a golf ball with a club.
2-3-m-2b-golfer-edexcel-gcse-physics  
Figure 2

The ball has a mass of 0.036 kg. The golf club is in contact with the ball for 2.5 × 10–4 s and the ball leaves the golf club at a speed of 40 m/s.

 
(i)

Calculate the momentum of the ball as it leaves the golf club to 2 significant figures.

[2]

       

(ii)

Calculate the average resultant force acting on the ball, while it is in contact with the golf club, to 2 significant figures.

[2]

2c3 marks

Higher Only

Figure 1 shows a hammer just before it hits a nail into some wood.

2-3-m-3c-edexcel-gcse-physics

Figure 3

The mass of the hammer is 400 g.

When it hits the nail, the hammer is travelling downwards with a velocity of 6.3 m/s.

Calculate the momentum of the hammer.

2d2 marks

Higher Only

The hammer comes to rest very soon after it hits the nail.


It takes 0.050 s for the hammer to become stationary.


Calculate the amount of force that causes this to happen.

Did this page help you?

3a3 marks

Higher Only

A person ice skating in Figure 1 throws a 0.20 kg tennis ball with a velocity of 30 m/s.

2-3-m-3a-skater-edexcel-gcse-physics

Figure 1

(i)
State the equation linking momentum, mass and velocity.
[1]
(ii)
Calculate the initial momentum of the snowball.

[2]

3b3 marks

Higher Only

The skater is moving forward when they throw the tennis ball.


This causes their speed to decrease.

 

Explain why this happens.

3c4 marks

Higher Only

The skater has a mass of 65 kg and they have an initial speed of 3.2 m/s.


Calculate their momentum after they have thrown the ball.

Ignore friction.

3d3 marks

Higher Only

The skater wears soft knee pads that compress easily.


Explain how the pads protect their knees when they fall on the ice.

Did this page help you?

4a3 marks

Higher only

Some cars have a pedestrian airbag for safety, as shown in Figure 1.

2-3-m-4a-safetybagcar-edexcel-gcse-physics

Figure 1

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.

4b4 marks

Higher Only

In a crash test a car drives through a thin wall.


The momentum of the car before the crash is 27 500 kg m/s. 

An average force with a magnitude of 50 kN acts on the car in the opposite direction to the car's motion over 0.30 s.

Calculate the final momentum of the car after it passes through the wall. 

4c4 marks

Higher Only

Car X is travelling down a road to the right at 15 m/s and has a mass of 500 kg.


Car Y is approaching car from behind at 22 m/s.

The total momentum of the system is 29 500 N s.

Calculate the mass of car Y.

4d4 marks

Higher Only

The driver of car Y is on their phone and they crash into the back of car X.

After the collision, both cars stick together and travel forward at the same speed. 

Calculate the combined speed of the cars.

Give your answer to 2 significant figures.

Did this page help you?

5a3 marks

Higher Only

A man is at a carnival playing a game to win a teddy bear.

He has to shoot pellets from a toy rifle at some cans filled with sand, as shown in Figure 1.

2-3-m-5a-carnival-game-edexcel-gcse-physics

Figure 1

He fires a pellet of mass 0.020 kg at the tins. The pellet moves at a velocity of 152 m/s. 

(i)
State the equation linking momentum, mass and velocity.
[1]
(ii)
Calculate the momentum of the pellet to 2 significant figures.
[2]
5b3 marks

Higher Only

The pellet becomes embedded in can 1, as shown in Figure 2.
2-3-m-5b-pellet-and-can-edexcel-gcse-physics
Figure 2
  

The mass of can 1 is 0.15 kg. The pellet and can 1 move away together.
 
Calculate the velocity of the pellet and can as they move together to 2 significant figures.

5c5 marks

Higher only

The man fires another identical pellet at the same speed at another can identical to can 1.

This time, however, the pellet bounces off with a velocity of −30 m/s.

Calculate the velocity of the can.

5d2 marks

Higher Only

The man misses and hits the table on which the cans rest.

Using the concept of inertia, explain why the table does not move as fast as the cans moved when hit.

Did this page help you?