MechanicsEdexcel A-Level Physics: Topic test

20 questions, 54 marks

Edexcel A-Level Physics

Mechanics topic test

Total 54 marks

Name

Class

Date

1
A sprinter accelerates uniformly from rest for the first 2.5 s of a 100 m race, reaching a speed of 9.0 m s⁻¹. She then runs at this constant speed until she crosses the finishing line.
(a)
What is her acceleration during the first 2.5 s?
[1 mark]
A0.28 m s⁻²
B3.6 m s⁻²
C23 m s⁻²
D1.8 m s⁻²
(b)
What distance does she cover in the first 2.5 s?
[1 mark]
A23 m
B5.6 m
C4.5 m
D11 m
(c)
Calculate the time she takes to complete the 100 m.
[2 marks]
Total for question 1: 4 marks
2
A dart is thrown horizontally at 6.0 m s⁻¹ towards a dartboard 2.40 m away. Air resistance may be ignored. Take g = 9.81 m s⁻².
(a)
How long does the dart take to reach the board?
[1 mark]
A0.40 s
B2.5 s
C14 s
D0.20 s
(b)
What is the vertical component of the dart's velocity as it reaches the board?
[1 mark]
A6.0 m s⁻¹
B7.2 m s⁻¹
C3.9 m s⁻¹
D9.8 m s⁻¹
(c)
Calculate the speed of the dart as it reaches the board.
[2 marks]
Total for question 2: 4 marks
3
A crate of mass 40 kg is released from rest on a rough ramp that is inclined at 25° to the horizontal. A constant frictional force of 80 N acts up the slope while the crate slides. Take g = 9.81 m s⁻².
(a)
Calculate the acceleration of the crate down the slope.
[3 marks]
(b)
The crate slides 5.0 m from rest. Calculate its speed after sliding this distance, and the work done against friction.
[4 marks]
Total for question 3: 7 marks
4
A toy cannon of mass 4.0 kg stands on smooth ice, initially at rest. It fires a ball of mass 0.020 kg horizontally at 400 m s⁻¹. The cannon is free to move and its mass is 4.0 kg once the ball has left. The propellant releases 2400 J of energy when it fires.
(a)
Explain, using Newton's third law and the conservation of momentum, why the cannon recoils, and calculate its recoil speed.
[6 marks]
(b)
Evaluate the energy changes in the firing, and calculate the efficiency with which the propellant's energy is transferred to kinetic energy.
[6 marks]
Total for question 4: 12 marks
5
A wheelbarrow carries a load that weighs 300 N. The load acts at a point 0.40 m horizontally from the axle of the wheel. The gardener lifts the handles with a vertical force F at a point 1.20 m horizontally from the axle, on the same side of the axle as the load (the load lies between the axle and the handles). The wheelbarrow is held at rest in equilibrium and its own weight may be ignored.
(a)
What is the moment of the load's weight about the axle?
[1 mark]
A750 N m
B360 N m
C120 N m
D12 N m
(b)
What is the force F exerted at the handles?
[1 mark]
A100 N
B120 N
C200 N
D900 N
(c)
Calculate the force exerted by the ground on the wheel.
[2 marks]
Total for question 5: 4 marks
6
A pump raises 600 kg of water every minute from a well 15 m deep and delivers it at the surface with negligible kinetic energy. The pump motor has an electrical input power of 2.0 kW. Take g = 9.81 N kg⁻¹.
(a)
What is the gain in gravitational potential energy of the water each minute?
[1 mark]
A9.0 × 10³ J
B1.5 × 10³ J
C1.2 × 10⁵ J
D8.8 × 10⁴ J
(b)
What is the efficiency of the pump system?
[1 mark]
A136%
B74%
C26%
D7.4%
(c)
Calculate the power wasted by the pump system and state where this energy goes.
[2 marks]
Total for question 6: 4 marks
7
A driver travelling at 25 m s⁻¹ sees a hazard ahead. After a reaction time of 0.70 s she applies the brakes, which produce a constant deceleration of 6.0 m s⁻² until the car stops.
(a)
Calculate the total distance the car travels from the moment the driver sees the hazard to the moment it stops.
[3 marks]
(b)
Calculate the average speed of the car over the whole stopping distance.
[4 marks]
Total for question 7: 7 marks
8
A uniform ladder of length 5.0 m and weight 200 N leans against a smooth vertical wall. Its foot rests on rough horizontal ground 3.0 m from the base of the wall, so the top touches the wall 4.0 m above the ground. The ladder is in equilibrium.
(a)
Calculate the force the wall exerts on the ladder, and explain why the ground must be rough.
[6 marks]
(b)
A painter of weight 700 N stands on the ladder 2.0 m along it from its foot. Calculate the new force from the wall and the force the ground exerts on the ladder, and state the Newton's third law pair of the wall's force.
[6 marks]
Total for question 8: 12 marks

End of questions

Written by the Exaim team, led by Shaun Daswani (Head of Upper Secondary, Improve ME Institute; MSc Financial Mathematics, Imperial College London; BSc, UCL) and Jason Daswani (operational lead, Improve ME Institute; LSE).