Energy Stores, Transfers and Calculations - Worksheets, Questions and Revision

20 original exam-style questions - 9 pages of questions with a full mark scheme - free printable PDF.

Download PDFJump to mark scheme (page 10)
« Previous: EnergyNext: Efficiency, Power and Energy Resources »
Revision Library
revisionlibrary.co.uk
GCSE · Physics

P1a Energy Stores, Transfers and Calculations

AQA 8464 · Calculator allowed · about 85 minutes
Total Marks
Name: _______________________________    Date: ____ / ____ / ______
Answer ALL questions. Show all your working.
1
Energy can be stored in different ways. Name the energy store most associated with each situation described below.
(a)A stretched elastic band, ready to fire a paper pellet.(1)
(b)A cyclist pedalling along a flat road at a constant speed.(1)
(c)A fully charged mobile phone battery.(1)
(d)A skydiver who has just jumped from a plane at a height of 3000 m, before they start to fall.(1)
(Total for Question 1 is 4 marks)
2
A ball is thrown vertically upwards from a person's hand. It rises, reaches a highest point, and falls back down. Air resistance is negligible.
(a)State what happens to the size of the kinetic energy store of the ball as it rises from the person's hand to its highest point.(1)
(b)State what happens to the size of the gravitational potential energy store of the ball over the same rise.(1)
(c)State which energy store is at its maximum value when the ball is at its highest point.(1)
(Total for Question 2 is 3 marks)
3
Conservation of energy is a fundamental principle in physics.
(a)State the principle of conservation of energy.(1)
(Total for Question 3 is 1 mark)
4
A go-kart has a mass of 150 kg and is travelling at a speed of 8 m/s. kinetic energy = 0.5 * mass * (speed)2
(a)Calculate the kinetic energy of the go-kart.(2)
(Total for Question 4 is 2 marks)
5
A shopping bag of mass 6 kg is lifted from the floor onto a shelf 1.8 m high. gravitational potential energy = mass * g * height. Take g = 9.8 N/kg.
(a)Calculate the gravitational potential energy gained by the bag.(2)
(Total for Question 5 is 2 marks)
6
An electric kettle transfers 138000 J of energy to the water inside it in 60 s. power = energy transferred / time
(a)Calculate the power of the kettle.(2)
(Total for Question 6 is 2 marks)
7
A student investigates the specific heat capacity of a 1.0 kg aluminium block using the required practical method. The block has two holes drilled into it: one holds an electrical heater connected to a joulemeter, and the other holds a thermometer. The block is wrapped in lagging. The heater is switched on and the block is heated for 10 minutes. change in thermal energy = mass * specific heat capacity * temperature change
(a)State why the block is wrapped in lagging.(1)
(b)The student records an initial temperature of 20.5 degreesC and a final temperature of 42.7 degreesC. Calculate the temperature change of the block.(1)
(c)The joulemeter shows that 20000 J of energy was supplied to the heater. Using this value, the mass of the block, and the temperature change from part (b), calculate the specific heat capacity of the aluminium block. Give your answer to 3 significant figures.(3)
(d)The accepted specific heat capacity of aluminium is 897 J/kg degreesC. Suggest one reason why the value calculated by the student in part (c) is higher than this accepted value.(1)
(Total for Question 7 is 6 marks)
8
A spring is compressed by 0.15 m. The spring constant is 250 N/m. Assume the spring does not exceed its limit of proportionality. elastic potential energy = 0.5 * spring constant * (extension)2
(a)Calculate the elastic potential energy stored in the spring.(3)
(Total for Question 8 is 3 marks)
9
A trolley of mass 2.5 kg is released from rest at the top of a track and rolls down to the bottom, a drop in height of 3.2 m. Assume the track is smooth (no energy is dissipated to the surroundings). Take g = 9.8 N/kg. gravitational potential energy = mass * g * height. kinetic energy = 0.5 * mass * (speed)2
(a)Calculate the gravitational potential energy lost by the trolley as it descends.(2)
(b)Using the principle of conservation of energy, calculate the speed of the trolley when it reaches the bottom of the track.(3)
(Total for Question 9 is 5 marks)
10
A crane lifts a load of mass 500 kg through a height of 12 m at a constant speed. Take g = 9.8 N/kg. gravitational potential energy = mass * g * height. power = energy transferred / time
(a)Calculate the gravitational potential energy gained by the load.(2)
(b)The crane takes 40 s to lift the load through this height. Calculate the power needed to lift the load at this constant speed, assuming all the energy supplied is transferred to the load's gravitational potential energy store.(2)
(Total for Question 10 is 4 marks)
11
An immersion heater with a power output of 1200 W is used to heat 2.5 kg of water from 18 degreesC to 45 degreesC. The specific heat capacity of water is 4200 J/kg degreesC. change in thermal energy = mass * specific heat capacity * temperature change. power = energy transferred / time
(a)Calculate the energy needed to raise the temperature of the water by this amount.(3)
(b)Calculate the minimum time needed for the heater to supply this energy, assuming no energy is lost to the surroundings.(3)
(Total for Question 11 is 6 marks)
12
Determining specific heat capacity accurately requires careful experimental technique.
Evaluate a method that could be used to determine the specific heat capacity of a liquid, such as water, in a school laboratory. In your answer you should refer to: the equipment and measurements needed, how energy losses to the surroundings could be reduced, and how the specific heat capacity would be calculated from the results.
(Total for Question 12 is 6 marks)
13
A bungee jumper of mass 65 kg jumps from a platform 40 m above a river. At the lowest point of the jump, the jumper is 5 m above the river surface and is momentarily at rest. Take g = 9.8 N/kg. gravitational potential energy = mass * g * height
(a)Calculate the loss in the jumper's gravitational potential energy between the platform and the lowest point of the jump.(2)
(b)State the energy store that this lost gravitational potential energy has mostly been transferred to by the time the jumper reaches the lowest point.(1)
(c)Assuming no energy is dissipated to the surroundings, calculate the elastic potential energy stored in the bungee cord at the lowest point of the jump.(1)
(Total for Question 13 is 4 marks)
14
Two identical-sized balls, A and B, are dropped from the same height above the ground at the same time. Ball A is made of solid rubber. Ball B is made of solid steel, which is denser than rubber, so ball B has a greater mass than ball A. Air resistance is negligible for both balls.
(a)State which ball, A or B, has the greater kinetic energy store just before it reaches the ground, and explain your answer.(3)
(Total for Question 14 is 3 marks)
15
The specific heat capacity of water is 4200 J/kg degreesC, aluminium is 897 J/kg degreesC, copper is 385 J/kg degreesC, and lead is 130 J/kg degreesC. change in thermal energy = mass * specific heat capacity * temperature change
(a)A 2 kg block of copper is supplied with 10000 J of energy. Calculate the temperature rise of the copper block.(2)
(b)A 2 kg block of lead is supplied with the same amount of energy (10000 J). Without calculating, state and explain which block, copper or lead, has the greater temperature rise.(1)
(Total for Question 15 is 3 marks)
16
A pendulum bob of mass 0.40 kg is pulled to one side so that it is raised 0.12 m above its lowest point, then released from rest. Assume no energy is dissipated to the surroundings. Take g = 9.8 N/kg. gravitational potential energy = mass * g * height. kinetic energy = 0.5 * mass * (speed)2
(a)Calculate the gravitational potential energy gained when the bob is raised.(2)
(b)Calculate the speed of the bob as it passes through its lowest point.(3)
(Total for Question 16 is 5 marks)
17
A 3 kW electric heater is used to transfer 5400000 J of energy to a room. power = energy transferred / time
(a)Calculate how long the heater was switched on for. Give your answer in minutes.(3)
(Total for Question 17 is 3 marks)
18
A student repeats the specific heat capacity experiment for an aluminium block three times, using the same energy input each time, and records temperature changes of 21.4 degreesC, 21.9 degreesC and 21.6 degreesC.
(a)Calculate the mean temperature change for the three repeats.(2)
(b)Suggest one reason why repeating the experiment and calculating a mean improves the student's results.(1)
(Total for Question 18 is 3 marks)
19
A lift (elevator) car of mass 1200 kg rises at a constant speed through a height of 25 m in 20 s. Take g = 9.8 N/kg. gravitational potential energy = mass * g * height. power = energy transferred / time
(a)Calculate the gravitational potential energy gained by the car.(2)
(b)Calculate the power needed to lift the car at this constant speed, assuming all the energy supplied to the motor is transferred to the car's gravitational potential energy store.(2)
(c)The lift is later fitted with a more powerful motor rated at 20000 W. Calculate the new minimum time needed to lift the car through the same height of 25 m, assuming the same amount of energy is required.(2)
(Total for Question 19 is 6 marks)
20
A ball of mass 0.058 kg is thrown vertically upward with an initial kinetic energy of 4.5 J. Assume all this kinetic energy is transferred to the gravitational potential energy store as the ball rises, with no energy dissipated to the surroundings. Take g = 9.8 N/kg. gravitational potential energy = mass * g * height
(a)Calculate the maximum height reached by the ball above the point where it was thrown.(3)
(Total for Question 20 is 3 marks)
Mark scheme · P1a Energy Stores, Transfers and Calculations

Question 1

Question 2

Question 3

Question 4

Question 5

Question 6

Question 7

Question 8

Question 9

Question 10

Question 11

Question 12

Question 13

Question 14

Question 15

Question 16

Question 17

Question 18

Question 19

Question 20