Y9 Energy Revision

• Physics
• Lower Secondary (Key Stage 3)

Give the 5 energy stores. What is each store associated with? Give an example of an object with a large store of each.

There are 5 ways energy is stored.

Store	Energy to do with...	For example...
Thermal	Objects that are hot.	A hot cup of tea.
Kinetic	Moving objects	A formula 1 car.
Chemical	Food and fuels	Batteries or coal.
Elastic potential	Objects that stretch or compress	A stretched rubber band.
Gravitational potential	Objects high up	A person standing on a diving board.

Usain Bolt running the 100m has a large store of...

1. Thermal energy
2. Elastic potential energy
3. Kinetic energy
4. Gravitational potential energy

Springs on a trampoline have a large store of...

1. Thermal energy
2. Elastic potential energy
3. Kinetic energy
4. Gravitational potential energy

A bonfire has a large store of...

1. Chemical energy
2. Kinetic energy
3. Elastic potential energy
4. Thermal energy

A chinese takeaway has a large store of...

1. Chemical energy
2. Kinetic energy
3. Elastic potential energy
4. Thermal energy

A clock hanging on the wall has a large store of...

1. Elastic potential energy
2. Thermal energy
3. Kinetic energy
4. Gravitational potential energy

A bullet train has a large store of...

1. Elastic potential energy
2. Thermal energy
3. Kinetic energy
4. Gravitational potential energy

The apple has 50 J of gravitational potential energy on the branch, how much kinetic energy does it have just before hitting the floor?

A rollercoaster has 120 J of kinetic energy, it moves up the slope until it comes to a stop. How much gravitational potential energy does the rollercoaster have when it stops?

How can energy be transferred?

A bonfire transfers energy to the thermal store of the air by...

1. Sound
2. Electricity
3. Heating
4. Force

How is energy transferred from a power source to a hairdryer?

1. Sound
2. Heating
3. Electricity
4. Force

Energy is transferred from the                          energy store of the battery to the radio by                         . The radio then transfers the energy by                         waves.

Energy within the                         energy store of your moving fingers is transferred to the                        energy store of a rubber band by                        .                

chemical

electricity

sound

kinetic

elastic

force

State the law of conservation of energy.

An object is more efficient if it transfers more energy in a USEFUL way.

What is the useful energy in this example?

1. Thermal (+ sound)
2. Kinetic

What is the useful energy in this example?

1. Thermal
2. Sound and kinetic

What is the useful energy in this example?

1. Kinetic
2. Sound
3. Thermal

Which car is the most efficient?

1. A
2. B

1. The filament lamp is most efficient.
2. The LED light is most efficeint.
3. The CFL lamp is most efficient.

How would you make a bike wheel more efficient?

1. Lubricant
2. Dampeners
3. Streamlined shape
4. Low electrical resistance

How would you make a mobile phone more efficient?

1. Lubricant
2. Dampeners
3. Streamlined shape
4. Low electrical resistance

How would you make a washing machine more efficient?

1. Lubricant
2. Dampeners
3. Streamlined shape
4. Low electrical resistance

How would you make an aeroplane more efficient?

1. Lubricant
2. Dampeners
3. Streamlined shape
4. Low electrical resistance