Year 7/8 Physical Science Energy Test

Match the definition to the type of energy:

• The energy of movement.

• Heat

• The energy associated with electric charges and their movements.

• Sound

• The thermal form of energy that involves warming, drying, burning and melting.

• Kinetic

• The energy of electromagnetic radiation that makes things visible.

• Light

• The energy that air has when it is vibrating.

• Electrical

The difference between the forms of energy listed above and potential energy is:

• Potential energy is stored energy, while the other forms are types of energy in use.

• Potential energy is always kinetic energy in motion.

• Potential energy cannot be converted to other forms of energy.

• Potential energy is the only form of energy that does not follow the law of conservation of energy.

List the four types of potential energy below:

• Gravitational potential energy, Elastic potential energy, Chemical potential energy, Nuclear potential energy

• Kinetic energy, Sound energy, Light energy, Heat energy

• Magnetic potential energy, Electrical energy, Solar energy, Wind energy

• Thermal energy, Mechanical energy, Radiant energy, Electrical energy

The law of conservation of energy states:

• Energy cannot be created or destroyed, but can be wasted.

• Energy can be created from nothing.

• Energy is always lost in every process.

• Energy can only be destroyed, not transformed.

Which of the following best illustrates the difference between energy transfers and energy transformations using flow charts with annotations?

• Energy transfers show energy moving from one object to another without changing form, while energy transformations show energy changing from one form to another within the same object.

• Energy transfers and energy transformations both show energy changing forms between objects.

• Energy transfers involve only heat energy, while energy transformations involve only kinetic energy.

• Energy transfers and energy transformations are the same and do not require different flow charts.

The energy transformations occurring in the two examples listed below are best described as:

• Conversion of potential energy to kinetic energy and thermal energy

• Conversion of chemical energy to electrical energy and sound energy

• Conversion of light energy to chemical energy and heat energy

• Conversion of electrical energy to mechanical energy and light energy

Heat energy is often identified as wasted energy because:

• it is usually transferred to the surroundings and cannot be usefully used, such as in a car engine where much energy is lost as heat.

• it is always completely converted into useful work in all machines.

• it increases the efficiency of all devices by being fully utilized.

• it is the only form of energy that can be stored indefinitely.

Select the correct energy flow equation for a smartphone playing a video.

• Chemical energy (battery) → Electrical energy → Light energy + Sound energy + Heat energy

• Light energy → Chemical energy → Sound energy + Heat energy

• Electrical energy → Chemical energy → Light energy + Sound energy

• Sound energy → Electrical energy → Light energy + Heat energy

Identify the correct energy flow equation for Scenario 2: A lit sparkler giving off sparks.

• Chemical energy → Heat energy + Light energy + Sound energy

• Electrical energy → Chemical energy → Light energy

• Kinetic energy → Chemical energy → Heat energy

• Light energy → Chemical energy → Sound energy

Identify the correct energy flow equation for Scenario 3: An ambulance is racing to the scene of an accident.

• Chemical energy (fuel) → Kinetic energy (motion) → Sound energy (siren) + Light energy (lights) + Heat energy (engine)

• Kinetic energy (motion) → Chemical energy (fuel) → Sound energy (siren) + Light energy (headlights)

• Sound energy (siren) → Chemical energy (fuel) → Kinetic energy (motion) + Heat energy (engine)

• Light energy (headlights) → Kinetic energy (motion) → Chemical energy (fuel) + Sound energy (siren)