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Name: _______________________________________________ Momentum Date: Time: Total marks available: Total marks achieved: ______ Page 1 of 29
Name: _______________________________________________
Momentum
Date:
Time: Total marks available: Total marks achieved: ______
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Questions
Q1.The diagram shows a roller-coaster ride.
The car is pulled slowly from the start to point B and then released.
(a) Choose letters from the diagram to complete this sentence.
(2)The car has the most gravitational potential energy at point .......................................
and it goes fastest at point ....................................... .
(b) The mass of the car is 900 kg.
The maximum speed of the car is 15 m/s.(i) State the relationship between momentum, mass and velocity.
(1)
(ii) Calculate the maximum momentum of the car.Give the unit.
(3)
maximum momentum = ........................... unit ...........................
(iii) State the equation linking kinetic energy (KE), mass and speed.(1)
(iv)Calculate the maximum KE of the car.(2)
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(Total for question = 9 marks)
Q2.Some quantities are vectors, others are scalars.
(a) Complete the table ticking the boxes to show which quantities are vectors and which are scalars.
One has been done for you.(2)
(b) A car travels at 20 m/s.
The mass of the car is 1500 kg.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the car.(2)
momentum = ........................................................... kg m/s
(c) In a crash test, a car runs into a wall and stops.The momentum of the car before the crash is 22500 kg m/s.
The car stops in 0.14 s.(i) Calculate the average force on the car during the crash.
(2)
average force = ........................................................... N
(ii) Use ideas about momentum to explain how seat belts can reduce injuries to passengers during a crash.(3)
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(Total for question = 10 marks)Q3.The driver of a car sees an obstacle in the road and stops the car as quickly as possible.
The car stops without hitting the obstacle.
State three factors that could have affected the stopping distance of the car.
(3)
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(Total for question = 3 marks)
Q5.This question is about collisions.
The diagram shows ball A moving in the direction shown by the arrow.
Ball A collides with ball B, a stationary ball of the same mass and size as ball A.
(a) State the principle of conservation of momentum.
(1)
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(b) Ball A collides with ball B.
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before the collision, ball A moves with a velocity of 10 m/s after the collision, ball B moves in the same direction as ball A with a velocity of 8 m/s ball A continues to move in the same direction, but at a lower velocity
Calculate the velocity of ball A after the collision. [mass of each ball = 0.16 kg]
(3)
velocity of ball A = ........................................................... m/s
(c) During the collision some kinetic energy is lost.
Calculate the kinetic energy lost in the collision.
(3)
kinetic energy lost = ........................................................... J
(Total for question = 7 marks)
Q7.A bowling ball rolls for 3 s and hits a pin.
The graph shows how the velocity of the ball changes with time.
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(a) How can the graph be used to find the distance that the ball rolls before it hits the pin?(1)
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(b) The mass of the ball is 6.4 kg.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the ball before it hits the pin.Give the unit.
(3)
Momentum = ........................................................... Unit ...........................................................(c) (i) What is the velocity of the ball after it hits the pin?
(1)
Velocity = ........................................................... m/s(ii) After the collision, the ball and the pin have the same velocity.Calculate the mass of the pin.
(3)
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Mass = ........................................................... kg
(Total for question = 9 marks)Q8.A rabbit runs across the road in front of a car.
The driver applies the brakes.
State four factors that affect the chance of the rabbit escaping without being hit.
(4)
1 ..............................................................................................................................................
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2 ..............................................................................................................................................
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(Total for question = 4 marks)Q9.The graph shows the minimum stopping distances, in metres, for a car travelling atdifferent speeds on a dry road.
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(a) Complete the equation to show the link between stopping distance, thinkingdistance and braking distance.
(1)Stopping distance =......................................................................................................................................(b) Describe the patterns shown in the graph.
(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(c) Use the graph to estimate the stopping distance for a car travelling at 35 miles per hour.
(1)
Stopping distance = ........................................................... m
(d) To find the minimum stopping distance, several different cars were tested.
Suggest how the data from the different cars should be used to give the values inthe graph.
(1) .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................(e) The tests were carried out on a dry road.
If the road is icy, describe and explain what change there would be, if any, to(i) the thinking distance
(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................
(ii) the braking distance(2)
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(Total for question = 9 marks)Q10.An ice skater throws a 0.23 kg snowball with a velocity of 13 m/s.
(a) (i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the initial momentum of the snowball.(2)
initial momentum = ....................................... kg m/s
(b) When the skater throws the snowball forwards, she slides backwards on the ice.
Explain why she moves in this direction.(3)
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(c) The skater wears soft knee pads that compress easily.
Explain how the pads protect her knees when she falls on the ice.(3)
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(Total for question = 9 marks)
Q12.(a) A student measures the weight of a cannonball as 50 N.
(i) Name a piece of equipment he could use to measure the weight.(1)
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(ii) State the equation relating weight, mass and g.(1)
(iii) Calculate the mass of the cannonball.(2)
mass ........................................................... kg
(b) Describe how the student could find the density of the cannonball.
You should include details of any further measurements he would need to make.(3)
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(c) A cannonball is fired from a cannon.
When the cannonball is fired, the cannon moves in the opposite direction, as shown in the diagram.
Using ideas about momentum, explain why the cannon moves in the opposite direction to the cannonball.(3)
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(Total for question = 10 marks)Q13.Scientists test the safety features of a car by crashing it into a large block of concrete.
A dummy is placed in the driver's seat and the scientists video the crash.
(a) In one test, the dummy and the car travel at 8 m/s.The mass of the dummy is 72 kg.Calculate the momentum of the dummy.
(2)
Momentum = ........................................................... kg m/s(b) In another test, the momentum of the dummy changes by 920 kg m/s in a timeof 0.17 s.
Calculate the average horizontal force acting on the dummy during this time.(2)
Average force = ........................................................... N
(c) These tests help to make our roads safer.(i) State two factors that affect the stopping distance of a car driven on a road.
(2)
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1 ..................................................................................................................................................................... ..............................................................................................................................................2 ..................................................................................................................................................................... ..............................................................................................................................................(ii) Use ideas about momentum to explain how the crumple zone of a car helps toreduce injuries during a crash.
(3) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................
(Total for question = 9 marks)Q14.(a) A boy of mass 43.2 kg runs and jumps onto a stationary skateboard.
The boy lands on the skateboard with a horizontal velocity of 4.10 m/s.(i) State the relationship between momentum, mass and velocity.
(1)
(ii) The skateboard has a mass of 2.50 kg.Using ideas about conservation of momentum, calculate the combined velocity of the boy and skateboard just after the boy lands on it.
(4)
combined velocity = ........................................................... m/s
(b) The boy holds a heavy ball as he stands on a stationary skateboard.
The boy throws the ball forwards while still standing on the skateboard.
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Explain what happens to the boy and the skateboard.(2)
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(Total for question = 7 marks)
Q15.A student is playing a game with some empty tins.
(a) He throws a wet cloth of mass 0.15 kg at the tins.The wet cloth moves at a velocity of 6.0 m/s.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the wet cloth and give the unit.(3)
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(iii) The wet cloth sticks to tin 1.
The mass of tin 1 is 0.050 kg.The cloth and tin 1 move away together.Calculate their velocity.
(2)
Velocity = ........................................................... m/s(b) The student throws a bigger wet cloth at the remaining tins.
This wet cloth sticks to tins 2 and 3 and they move away together.
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The student concludes
Do you agree with this conclusion?Explain why.
(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................
Total for question = 8 marks)Q16.A lorry carries a load of hot asphalt – a runny mixture of small stones and tar.
(a) The mass of the lorry and its load is 17 000 kg.The velocity is 13 m/s.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Calculate the total momentum of the lorry and its load.(2)
momentum = ........................................................... kg m/s
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(b) The lorry stops suddenly and the load slides to the front, as shown below.
Force A and force B are upward forces from the road on the lorry.(i) Use ideas about momentum to explain why the load slides to the front whenthe lorry stops suddenly.
(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ..............................................................................................................................................
(ii) Use ideas about moments to explain why force B increases when the loadslides to the front.
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(c) The force on the road from one of the tyres is 53 000 N.The pressure of the air in this tyre is 390 kPa.(i) State the equation linking pressure, force and area.
(1)
(ii) Calculate the area of this tyre in contact with the road.(2)
Area = ........................................................... m2
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(Total for question = 11 marks)Q17.Some cars have a pedestrian airbag for safety.
If a pedestrian is hit and lands on the front of the car, the airbag inflates.
Use ideas about momentum to explain how this airbag can reduce injuries to pedestrians.
(4)
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(Total for Question = 4 marks)
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Q18.Newton's Cradle consists of a set of identical solid metal balls hanging by threadsfrom a frame so that they are in contact with each other.
(a) A student initially pulls ball A to the side as shown.The student releases ball A and it collides with ball B.(i) State the equation linking momentum, mass and velocity.
(1)
(ii) Each ball has a mass of 100 g.At the time of collision, ball A has a velocity of 3m/s.Calculate the momentum of ball A at the time of impact and give the unit.
(3)
momentum ........................................................... unit ...........................................................
(iii) After the collision, ball A stops. Ball E moves away. The other balls remain still.
The momentum of ball E as it moves away is the same as the momentum ofball A at the time of impact.Give the reason for this.
(1) .............................................................................................................................................. ..............................................................................................................................................
(b) The student then releases balls A and B together as shown below.
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Predict what will happen to the other balls after the collision and give a reason foryour answer.
(2) .............................................................................................................................................. .............................................................................................................................................. .............................................................................................................................................. ...............................................................................................................................................
(Total for question = 7 marks)Q19.The photograph shows a hammer just before it hits a nail.
(a) The mass of the hammer is 0.50kg.
When it hits the nail, the hammer is travelling downwards with a velocity of 3.1m/s.(i) State the relationship between momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the hammer.(2)
momentum = ........................................................... kg m/s
(iii) The hammer stops quickly when it hits the nail.The momentum of the hammer reduces to zero in 0.070s.
Calculate the amount of force that causes this to happen.(2)
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force = ........................................................... N
(b) As it enters the wood, the nail exerts a force on the wood.
At the same time, the wood exerts a force on the nail.
Explain how these two forces are related.(2)
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(c) Both ends of the nail exert pressure when the nail goes into the wood.
Explain why the nail exerts more pressure on the wood than it does on the hammer.(2)
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(Total for question = 9 marks)
Q20.The table gives some measurements about a raindrop.
(a) (i) State the relationship between momentum, mass and velocity.
(1)
(ii) Calculate the momentum of the raindrop as it hits the ground.Give the unit.
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(3)
momentum = .............................. unit ..............................
(b) (i) State the equation linking gravitational potential energy, mass, g and height.
(1)
(ii) Calculate the change in gravitational potential energy (GPE), when the raindrop falls 1200 m above the ground.
(2)
GPE = ........................................................... J
(iii) State the kinetic energy (KE) of the raindrop as it hits the ground.[assume no energy losses]
(1)
KE = ........................................................... J
(c) (i) State the equation linking kinetic energy, mass and speed.
(1)
(ii) Show that the speed of the raindrop as it hits the ground would be about 150 m/s.[assume no energy losses]
(3)
(iii) Explain why the actual speed of the raindrop as it hits the ground is much less than 150 m/s.(2)
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(Total for question = 14 marks)
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