P1: energy

Question 1

Give the eight energy stores.

Answer 1

• Thermal
• Kinetic
• Gravitational potential
• Elastic potential
• Chemical
• Magnetic
• Electrostatic
• Nuclear

Question 2

What is work done?

Answer 2

Work done is energy transferred.

Question 3

Define specific heat capacity.

Answer 3

Specific heat capacity is the amount of energy required to raise the temperature of 1 kg of a substance by 1 degree C.

Question 4

Give a method that a student could use investigate the specific heat capacity of a material.

Answer 4

• Find a block of the material you want to investigate that has two holes in it.
• Measure the mass if the block, then wrap it in a layer of insulation.
• Insert a heater and a thermometer into the holes of the block. The heater should be connected to a power supply and an ammeter.
• Measure the initial temperature and set the potential difference of the power supply to 10V.
• Turn on the power and start a stopwatch.
• As the block heats up, take readings of the temperature and current every minute for 10 minutes.
• Use P=VI and E = Pt to the energy transferred to the heater, and use the recorded data to plot a graph of energy transferred. Use the gradient of the graph to find the SHC: 1/gradient x mass.

Question 5

What is the conservation of energy principle?

Answer 5

Energy cannot be created or destroyed

Question 6

What is power?

Answer 6

Power is the rate of doing work

Question 7

Give a way of reducing friction, and a way of reducing unwanted heat transfer.

Answer 7

Lubrication, and insulation

Question 8

Give two ways of insulating a house.

Answer 8

Loft insulation
Double glazing
Cavity walls

Question 9

What is a biofuel?

Answer 9

A biofuel is a fuel made of organic material, like dead plants or animal waste.

Question 10

Give an advantage and a disadvantage of wind power

Answer 10

• No pollutants released
• Noisy and eyesore

Question 11

Give an advantage and a disadvantage of solar power

Answer 11

• No pollutants released
• Only produces energy in sunny weather or daytime.

Question 12

Give an advantage and a disadvantage of geothermal power

Answer 12

• Not many suitable locations for plants
• Free, reliable energy (after costs of building)

Question 13

Give an advantage and a disadvantage of hydroelectric power

Answer 13

• Possible loss of habitat for some species
• Can provide a large amount of energy at a short notice.

Question 14

Give an advantage and a disadvantage of biofuels

Answer 14

• In some regions, large areas of land have been cleared specifically to grow biofuels.
• Reliable, as crops take a fairly short amount of time to grow.

Question 15

Give an advantage and a disadvantage of non-renewable energy.

Answer 15

• Very cheap and reliable
• Will run out