Physics

Question 1

Energy

Answer 1

The ability to do work. Measured in Joules (J)

Question 2

Energy Store

Answer 2

How energy is kept by an object until it is ready to be used

Question 3

Energy Transfer

Answer 3

How energy is moved from one object or place to another

Question 4

Conservation of energy

Answer 4

Energy cannot be created nor destroyed. Only moved from one store to another

Question 5

Dissipate

Answer 5

When energy is transferred to the thermal store of its surroundings, we say that it has dissipated

Question 6

Power

Answer 6

The rate at which energy is transferred P=E/T

Question 7

Watt (W)

Answer 7

Unit of Power

Question 8

Efficiency

Answer 8

The more energy something wastes the less efficient it is

Question 9

Sankey diagram

Answer 9

A diagram that shows the efficiency of a machine

Question 10

What are the 8 energy stores

Answer 10

Magnetic, Kinetic, Thermal, Gravitational potential, Electrostatic, Chemical, Elastic Potential, Nuclear

Question 11

Describe the energy transfer that occurs as a ball falls to the ground

Answer 11

Gravitational potential - Kinetic

Question 12

Where does energy end up at the end of most energy transfers?

Answer 12

In the Thermal Store of the surroundings

Question 13

How do you convert KW into W?

Answer 13

Multiply by 1000

Question 14

How do you convert W into KW?

Answer 14

Divide by 1000

Question 15

What is the formula for efficiency

Answer 15

Useful energy out ÷ Total energy in
or
useful power out ÷ Total power in

Question 16

Give the equation for finding Kinetic Energy

Answer 16

Ek = 0.5 x m x v2

Question 17

Give the equation for finding gravitational potential energy

Answer 17

Ep = m x g h

Question 18

Spring Constant

Answer 18

It measures how difficult it is to compress or stretch a spring. The larger the number, the harder it is to compress a spring

Question 19

Specific Heat Capacity

Answer 19

How much energy is needed to heat up 1kg of a material by a temperature of 1’c

Question 20

Thermal conductivity

Answer 20

Tells how well a material conducts heat. The higher the thermal conductivity of a material the higher the rate of energy transfer

Question 21

Renewable energy source

Answer 21

The source of energy cannot be used up or can be replenished

Question 22

Non-renewable energy source

Answer 22

It is finite - will eventually run out

Question 23

National grid

Answer 23

A network of cables and transformers to distribute electricity to homes schools business and hospitals

Question 24

What is the formula for Elastic Potential energy

Answer 24

Ee = 1/2 x k x e2

Where k is the spring constant measured in Newtons per metre

Question 25

Give the equations for specific heat capacity

Answer 25

▲E= m x c ▲

Question 26

Give four ways to prevent unwanted energy transfers in a home

Answer 26

Cavity walls, Loft insulation, Double glazed windows, draught excluders

Question 27

Name 4 non renewable energy sources

Answer 27

Coal, oil, gas and nuclear

Question 28

Name 7 renewable energy sources

Answer 28

Solar, Wind, Wave, Tidal Wave, Hydroelectric, Biofuel, Geothermal,

Question 29

Give two disadvantages of burning fossil fuels

Answer 29

Burning fossil fuels releases carbon dioxide (causes global warming) and sulphur dioxide (acid rain)

Question 30

What are trnasformers

Answer 30

Step up transformers increase the potential difference in the cables Step down transormers decrease the potential difference in cables