Energy 1 revision

Which energy store is usefully transferred to in a blender

• The kinetic store of the blades

• The elastic potential energy of the blades

• The magnetic energy store of the blades

The amount of energy transferred by an appliance depends on...

• Its power and size

• its power and mass

• Its power and the time it is on for

What happens to the amount of energy in a car's kinetic energy store when the car slows down?

• It remains the same.

• It decreases as some energy is transferred away to different stores

• It decreases as some energy is destroyed

When an object falls from a height, the maximum energy transferred to its kinetic energy store is equal to...

• …the energy transferred to its gravitational potential energy store

• …the energy transferred away from its gravitational potential energy store

What is the name of a system in which there is no net (overall) change in the total energy

• A closed system

• An open system

• A mechanical system

800 J of energy is supplied to a toaster with an efficiency of 25%. What is the useful output of the toaster?

• 200 J

• 775 J

• 1000 J

When a racket hits a ball, energy is transferred from the racket's kinetic energy store to the ball's kinetic energy store. This energy is transferred...

• by heating

• electrically

• mecahnically

Electric heater A has a power rating of 1 kW. Electric heater B has a power rating of 880 W. Which transfers the most energy in 2 hours?

• Heater A

• Heater B

True or false? "A toaster with a power of 4W transfers 4 J of energy per minute"

• True

• False

The rate of energy transfer from a house can be reduced by...

• …having walls with a low thermal conductivity

• …having walls with a high thermal conductivity