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Question 1

Define energy

Answer 1

The ability for something to do work.

Question 2

Define conservation of energy

Answer 2

Can’t be created or destroyed. It can transfer between stores.

Question 3

Give the unit of energy

Answer 3

Joules (J).

Question 4

Name the 7 different energy stores

Answer 4

Chemical, gravitational, kinetic, nuclear, thermal, electromagnetic, elastic

Question 5

Identify which store of energy is associated with objects raised above the earth’s surface

Answer 5

Gravitational.

Question 6

Identify which store of energy is associated with hot objects

Answer 6

Thermal.

Question 7

Identify which store of energy is associated with moving objects

Answer 7

Kinetic.

Question 8

Identify which store of energy is associated with objects that have been stretched

Answer 8

Elastic.

Question 9

Identify which store of energy is associated with the nucleus of an atom

Answer 9

Nuclear.

Question 10

Identify which store of energy is associated with the energy stored in bonds between atoms

Answer 10

Chemical.

Question 11

Identify which store of energy is associated with charged or magnetised objects

Answer 11

Electromagnetic.

Question 12

Give the equation for calculating weight

Answer 12

Weight = mass x gravity

Question 13

Give the equation for calculating work done

Answer 13

Work done = force x distance

Question 14

Give the equation for calculating Kinetic Energy

Answer 14

Kinetic energy = 0.5 x mass x speed²

Question 15

Give the equation for calculating Gravitational Potential Energy

Answer 15

Gravitational potential energy = mass x gravity x change in height

Question 16

Give the equation for calculating force applied to a spring

Answer 16

Force applied = spring constant x extension

Question 17

Give the equation for calculating efficiency of energy or power

Answer 17

Efficiency = useful output (energy or power) / total input (energy or power)

Question 18

Define efficiency

Answer 18

A measure of the useful energy transferred by an object compared to the total amount of energy it uses.

Question 19

Describe how the efficiency of a machine can be improved

Answer 19

Lubricate moving parts to reduce friction. Secure all screws to reduce vibrations. Use streamline shapes.

Question 20

Give the equations for calculating power

Answer 20

Power = work done / time; Power = energy transferred / time

Question 21

Define power

Answer 21

The amount of energy transferred by an object each second.

Question 22

Give the unit of power

Answer 22

Watts (W).