Work, energy and power — AS & A Level Physics (9702) questions by topic
Expect projectile motion timed across a curved path, frictionless slopes at an angle theta, engine efficiency and resistive force from a car's power output, and system efficiency from useful versus wasted power, worth from 1 to 15 marks in this A Level Physics set.
Calculate and show top the command words here, alongside identify, deduce and state: show demands every step of a derivation on the page, not just a final number. 70 real questions from 2023 to 2025 papers are collected below. Work through momentum-change calculations line by line and submit for instant marking, since a wrong sign on velocity or a substituted final-instead-of-change momentum value is exactly what examiners flag.
What examiners look for
- Examiners repeatedly find the weakest candidates use a block's initial momentum value as if it were its initial velocity.
- A common error is not carefully tracking direction, leading to at least one momentum value substituted with the wrong sign.
- Reports note candidates using the final momentum of a block instead of calculating its change in momentum.
- Another frequent mistake is using the difference between two blocks' momentums rather than the change in momentum of just one block.
May–June 2025, Paper 11
Leonardo da Vinci proposed a flying machine that would work like a screw to lift the pilot into the air. The 'screw' is rotated by the pilot. The machine and the pilot together…
Answer this question and get it marked →An object is falling in a uniform gravitational field. Which two quantities are sufficient to calculate the change in gravitational potential energy? A mass and acceleration of…
Answer this question and get it marked →The points X, Y and Z are on a rough, horizontal surface. The distance from X to Y is 3.0 m (vertically above Y). A box P is pushed across the surface from X to Y and then from Y…
Answer this question and get it marked →The momentum of a car of mass m increases from p₁ to p₂. What is the increase in the kinetic energy of the car? A (p₂² − p₁²) / (2m) B (p₂ − p₁)² / (2m) C (p₂ − p₁) / (2m) D (p₁ −…
Answer this question and get it marked →A parachutist is falling at constant (terminal) velocity. Which statement is not correct? A Gravitational potential energy is converted into kinetic energy of the air. B…
Answer this question and get it marked →May–June 2025, Paper 12
A ball of mass 1.2 kg travels horizontally at a speed of 3.0 m s^-1. The ball hits a cushion and comes to rest over a horizontal distance of 0.020 m. What is the work done by the…
Answer this question and get it marked →A box of mass 4.9 kg is pushed at a constant velocity from point P at the bottom of an inclined plane to point Q at the top. The box is pushed by a force of 64 N acting parallel…
Answer this question and get it marked →Which expression gives the efficiency of a system? A total energy input / useful energy output B (useful energy output + wasted energy output) / total energy input C useful energy…
Answer this question and get it marked →May–June 2025, Paper 13
Four identical blocks, each of mass m and thickness h, are stacked on top of each other. The blocks start with all four lying on the ground side by side and are then stacked into…
Answer this question and get it marked →A motor has an input power of 1.7 kW and an efficiency of 53%. What is the useful output power of the motor? A 0.80 kW B 0.90 kW C 1.1 kW D 1.2 kW
Answer this question and get it marked →A ball is released from rest and falls freely under gravity. The ball is dropped from a height H above the ground. Which graph correctly shows the variation of kinetic energy EK…
Answer this question and get it marked →An object moves with speed 10 m/s and has kinetic energy 1500 J. The speed of the object is then increased to 40 m/s. What is the new kinetic energy of the object? A 6000 J B 8000…
Answer this question and get it marked →May–June 2025, Paper 14
In which situation is work done on an object? A The object slides with a constant velocity along a horizontal frictionless surface in a vacuum. B A person holds the object at…
Answer this question and get it marked →An electric motor operating a lift has an output power of 20 kW. The lift and passengers have a combined mass of 1500 kg. The motor raises the lift at constant speed through a…
Answer this question and get it marked →In which situation is the least amount of energy transferred? A A student and a motorcycle of total mass 80 kg come to rest from a speed of 2.0 m s⁻¹. B A student of mass 50 kg…
Answer this question and get it marked →May–June 2025, Paper 21
May–June 2025, Paper 23
A car of mass 1500 kg is travelling along a straight horizontal road at constant velocity v. The car is subject to a total resistive force F. Show that the power P developed by…
Answer this question and get it marked →May–June 2025, Paper 24
A block of mass 5.5 kg falls vertically and hits a vertical spring. At the moment of contact with the spring, the kinetic energy of the block is 110 J. Calculate the speed of the…
Answer this question and get it marked →May–June 2025, Paper 54
A student investigates the relationship between the luminosity of a star and its mass. The student obtains data of relative luminosity λ and relative mass μ for six stars, where λ…
Answer this question and get it marked →May–June 2024, Paper 11
A box of weight 40 N is pushed with a horizontal force of 20 N along level ground for a distance of 2.4 m. The box is then lifted at constant velocity through a height of 1.6 m by…
Answer this question and get it marked →Which statement about efficiency is correct? A Efficiency does not have a unit. B The joule is a unit of efficiency. C The metre is a unit of efficiency. D The watt is a unit of…
Answer this question and get it marked →A steel ball is falling at constant speed in oil. Which graph shows the variation with time of the gravitational potential energy Eₚ and the kinetic energy Eₖ of the ball? A Eₚ…
Answer this question and get it marked →May–June 2024, Paper 12
The force resisting the motion of a car is proportional to the square of the car's speed. The magnitude of the force at a speed of 20.0 m s⁻¹ is 800 N. What useful output power is…
Answer this question and get it marked →A box of weight W is pulled by a force P along a slope. The length of the slope is d, and the box rises a height h. The frictional force between the box and the slope is F. The…
Answer this question and get it marked →The kinetic energy of a particle is increased by a factor of 4. By what factor does its speed increase? A 2 B 4 C 8 D 16
Answer this question and get it marked →A mass of 28 g is raised vertically upwards through a distance of 4.6 m. What is the change in gravitational potential energy of the mass? A 0.13 J B 1.3 J C 130 J D 1300 J
Answer this question and get it marked →May–June 2024, Paper 13
In many filament lamps, as much as 92 J of energy is emitted as thermal energy for every 8 J of energy emitted as light. What is the efficiency of a filament lamp, as the…
Answer this question and get it marked →What is a unit of power? A J C⁻¹ B J m⁻¹ C J N⁻¹ D J s⁻¹
Answer this question and get it marked →An object is in a uniform gravitational field. The graph shows how the change in gravitational potential energy ΔEₚ of the object varies with the vertical distance x moved by the…
Answer this question and get it marked →A block of mass 2.0 kg is released from rest on a slope. It travels 7.0 m down the slope and falls a vertical distance of 3.0 m. The block experiences a frictional force parallel…
Answer this question and get it marked →October–November 2024, Paper 11
A car of mass 1200 kg has momentum 18 000 kg m s^-1. What is the kinetic energy of the car? A 4.65 kJ B 6.57 kJ C 135 kJ D 270 kJ
Answer this question and get it marked →A ball of mass m is thrown up to height h in air with an initial velocity v, as shown. The ball travels from point P up to maximum height h and back down to point Q at the same…
Answer this question and get it marked →A torch uses three lamps connected in parallel and is powered by a cell of electromotive force (e.m.f.) 3.0 V and negligible internal resistance. Each lamp dissipates 0.60 W of…
Answer this question and get it marked →October–November 2024, Paper 12
A small car travels in a town. What is a reasonable estimate of the kinetic energy of the car? A 5 x 10^4 J B 5 x 10^7 J C 5 x 10^10 J D 5 x 10^13 J
Answer this question and get it marked →A moving object strikes a stationary object. The collision is inelastic. The objects move off together. Assume that the two objects form an isolated system. Which row shows the…
Answer this question and get it marked →What is the definition of power? A work done in one second B work done in unit time C work done per second D work done per unit time
Answer this question and get it marked →A model car travels at a constant velocity of 12 m s^-1 in a straight horizontal line. The input power to the engine of the car is 800 W. The efficiency of the engine is 60%. What…
Answer this question and get it marked →Which statement represents the principle of conservation of energy? A Energy cannot be used faster than it is created. B The supply of energy is limited, so energy must be…
Answer this question and get it marked →A barrel of mass 50 kg is loaded onto the back of a lorry 1.6 m high by pushing it up a frictionless plank 3.4 m long. What is the minimum work done? A 80 J B 170 J C 780 J D 1700…
Answer this question and get it marked →The graph shows how the length of a spring varies with the force applied to it. Two areas P and Q are labelled: area P is the triangular region between the graph line and the…
Answer this question and get it marked →October–November 2024, Paper 13
A stone of mass 0.30 kg is thrown vertically downwards with a speed of 20 m s^-1 from a height of 12 m above the ground. It falls vertically until it hits the ground. Air…
Answer this question and get it marked →A weight W hangs from a trolley that runs along a rail. The trolley moves horizontally through a distance p and simultaneously raises the weight through a height q. As a result,…
Answer this question and get it marked →The equation for kinetic energy EK can be derived using the equations of motion. Four equations relating to motion are listed. 1 W = F s 2 F = m a 3 v^2 = u^2 + 2 a s 4 P = W / t…
Answer this question and get it marked →The potential difference (p.d.) across a fixed resistor is V. The power dissipated in the resistor is 5.0 W. The p.d. across the resistor then changes to a new value. With the new…
Answer this question and get it marked →October–November 2024, Paper 21
State what is meant by the work done by a force.
Answer this question and get it marked →October–November 2024, Paper 22
Define electric potential difference (p.d.).
Answer this question and get it marked →February–March 2023, Paper 12
A system with an efficiency of 74% wastes 230 W of power. What is the useful output power of the system? A 170 W B 310 W C 650 W D 880 W
Answer this question and get it marked →A projectile of mass 0.25 kg is at a height of 30 m above horizontal ground and travelling at a speed of 15 m s^-1. A short time later, it is at a height of 35 m above the…
Answer this question and get it marked →A wire carries a current of 0.10 uA. The potential difference across the wire is 10 mV. How much energy is dissipated by the wire in a time of 10 s? A 1.0 pJ B 10 pJ C 1.0 nJ D 10…
Answer this question and get it marked →February–March 2023, Paper 22
Two blocks slide directly towards each other along a frictionless horizontal surface, as shown in Fig. 4.1. The blocks collide and then move as shown in Fig. 4.2. Block X…
Answer this question and get it marked →May–June 2023, Paper 11
A man sits on a buggy that is pulled along by a wire attached to a kite. The wire is at an angle of 40 degrees to the horizontal and has a constant tension of 200 N. The man and…
Answer this question and get it marked →A ball is thrown vertically upwards from the surface of the Earth. Which statement describes the energy of the ball as it rises through the air? A The kinetic energy of the ball…
Answer this question and get it marked →May–June 2023, Paper 12
A steam turbine is used to drive a generator. The input power to the turbine is PI and the output power is PO. The power loss in the turbine is PL. What is the efficiency of the…
Answer this question and get it marked →A variable force is applied to ensure that a constant power is supplied to a train. Which graph best shows the variation of the force F applied with the velocity v of the train? A…
Answer this question and get it marked →A block is released from rest and slides a distance x down a straight slope. The slope is at an angle theta to the horizontal. The slope is frictionless and air resistance is…
Answer this question and get it marked →A resistor of resistance R is connected across a cell of electromotive force (e.m.f.) E and negligible internal resistance. Which single change to the circuit would lead to the…
Answer this question and get it marked →May–June 2023, Paper 13
An airport has a mechanical system for moving luggage. The system uses a horizontal conveyor belt, a sloping conveyor belt, a lift and a frictionless slide. Resistive forces…
Answer this question and get it marked →A car moves along a horizontal road with a constant velocity v against a resistive force F. The engine of the car has an efficiency of 25%. What is the input power to the engine?…
Answer this question and get it marked →An object of mass 0.40 kg is projected into the air and follows a curved path above horizontal ground. The object takes a time of 1.5 s to move along its path. The object lands a…
Answer this question and get it marked →May–June 2023, Paper 21
October–November 2023, Paper 11
A crate of mass 50 kg is pushed a distance of 6.0 m along a horizontal surface against a constant resistive force of 70 N. The crate moves at a constant speed. It is then lifted,…
Answer this question and get it marked →The input power to a television is Pin. The useful sound and light power emitted by the television is Pout. What is the efficiency of the television? A Pout / Pin B (Pin - Pout) /…
Answer this question and get it marked →In the circuit shown, the battery has an electromotive force (e.m.f.) of 6.0 V and negligible internal resistance. The three resistors each have resistance R: one resistor is…
Answer this question and get it marked →October–November 2023, Paper 12
Two balls, of masses m and 2m, travelling in a vacuum with initial velocities 2v and v respectively, collide with each other head-on. After the collision, the ball of mass m…
Answer this question and get it marked →An electric car travels at a constant speed of 70 km h^-1 for 80 km on a straight horizontal road and uses energy E from its battery. The total resistive force acting on the car…
Answer this question and get it marked →What is meant by the efficiency of a system? A the total energy input to the system divided by the useful energy output by the system B the useful energy output from the system…
Answer this question and get it marked →In the circuit shown, a fixed resistor X is connected in series with a battery and a variable resistor. The power dissipated in resistor X is 7.2 W when a current of 3.0 A passes…
Answer this question and get it marked →October–November 2023, Paper 13
A wooden cylinder floats partially submerged in a bath of water. A force F is applied to the cylinder until it is just fully submerged. Which statement is not correct? A Some of…
Answer this question and get it marked →A system has a useful power output of 4.0 W and a wasted power of 16 W. What is the efficiency of the system? A 5.0% B 20% C 25% D 80%
Answer this question and get it marked →A parachutist is falling towards the ground at a constant speed v. The rate at which she is losing gravitational potential energy is R. The acceleration of free fall is g. What is…
Answer this question and get it marked →Other AS & A Level Physics topics
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