Energy Stores and Systems

Pages 17-19

Write down four energy stores.

Possible answers:

• Thermal

• Kinetic

• Gravitational Potential

• Elastic Potential

• Chemical

• Magnetic

• Electrostatic

• Nuclear

What is a system?

A single object or a group of objects that you are interested in

Describe the energy transfers that occur when a car collided with a stationary object.

The normal contact force causes energy to be transferred from the car’s kinetic energy store to other energy stores

If energy is transferred to an object’s kinetic energy store, what happens to its speed?

It speeds up

Give the equation for finding the energy in an object’s gravitational potential energy store

E = mgh

Give the equation for finding the energy in an object’s kinetic energy store

E = 1/2mv²

Give the equation for finding the energy in an object’s elastic potential energy store

E = 1/2ke²

What kind of energy store is energy transferred to when you compress a spring?

Elastic potential energy

What does the variable “e” stand for in the equation for energy in an elastic potential energy store?

Extension

When something is dropped from a height, what is it accelerated by and what force does work?

• Accelerated by gravity

• Gravitational force does work

When can work be done?

• When current flows

• By a force moving an object