Energy is measured in the unit
What is Joules
A person running mainly has this type of energy
What is kinetic energy
This happens when energy moves from one object to another but stays in the same form
What is energy transfer
Energy that helps a device do its intended job is called this
What is useful energy
Heat always moves from a warmer object to this type of object
What is a cooler object
The ability to do work
What is energy
A stretched rubber band stores this type of energy
What is elastic potential energy
This happens when energy changes from one form to another
What is energy transformation
Energy that is not useful is often released as these two forms
What are heat and sound energy
Heat transfer through direct contact is called this
What is conduction
This form of energy is found in moving objects
What is kinetic energy
As an object’s speed increases, its kinetic energy does this
What is increases
When a soccer player kicks a ball, kinetic energy is passed from the player’s leg to the ball. This is an example of this
What is energy transfer
This is the formula for energy efficiency
What is useful energy ÷ total input energy × 100
Materials such as wood, rubber and plastic are poor conductors and are also called this
What are insulators
This type of potential energy is stored in food, batteries and fuels
What is chemical potential energy
If two objects move at the same speed, the object with greater mass has this amount of kinetic energy
What is more kinetic energy
A battery-powered torch changes chemical potential energy into electrical energy and then light energy. This is an example of this
What is energy transformation
A remote-control car uses 1800 J of energy and produces 450 J of useful kinetic energy. Its efficiency is this percentage
What is 25%
Heat transfer through the movement of liquids or gases is called this
What is convection
This type of potential energy is stored in objects above the ground
What is gravitational potential energy
A pot plant placed higher on a wall has more of this type of energy
What is gravitational potential energy
In a solar panel system, light energy is changed into electrical energy, then stored as this type of energy in batteries
What is chemical potential energy
LED globes are more energy efficient than incandescent globes because they produce more useful light energy and less of this wasted energy
What is heat energy
Dark colours get warmer in sunlight because they absorb more of this type of energy
What is radiant energy/radiation