Energy stored in a moving object is called kinetic energy. As an object is raised above ground its gravitational potential energy increases. When a force moves an object work is done.
Which is a correct example of work being done?
An apple sitting still on a table
A shelf holding up a book
A toy car being pushed across the floor
What are the correct units for work?
Work is measured in joules (J)
Work is measured in amps (A)
Work is measured in newtons (N)
How much work is done by a 10 N force pushing a box 4 m across the floor?
If a motor does 500 J of work to lift a 200 N weight, how high was the weight lifted?
What is the gravitational potential energy stored in a 60 kg child sitting at the top of a 2 m high slide? (g = 10 N/kg)
What is the name of the energy stored by a moving object?
Gravitational potential energy
What is the main energy transfer for an apple falling from a tree?
Kinetic energy → gravitational potential energy
Chemical energy → gravitational potential energy
Gravitational potential energy → kinetic energy
Which of the following is a definition of power?
The amount of work done by a certain force
The energy transferred × time taken
The amount of work done ÷ time taken
A hairdryer transforms 10,000 J of energy in 4 s. What is its power?
A 60 W lamp is left on for 20 s. How much energy has been transformed?