Science Chapter 15 Section 1

Energy

ability to do work or cause a change

• work is done when a force moves an object through a distance

• energy is is transferred by a force moving an object though a distance

Two types of energy:

Kinetic and potential

Kinetic energy

energy of motion

Kinetic energy of any objects depends on two things:

mass and speed

Potential Energy

stored energy as a result of position or shape

Two forms of potential energy:

elastic potential energy and gravitational potential energy

Elastic potential energy

can be stretched or compressed

Gravitational potential energy

• depends on mass, height from ground, and acceleration due to gravity

• Potential energy

• Example: person on top of a mountain

Mechanical energy

• Objects movement creates energy

• energy associated with the motion and position of everyday objects

• Both Potential and Kinetic energy

• Examples: PE= bow being pulled & KE= person cycling

Thermal energy

• The vibration and movement of molecules

• Atoms move faster = thermal energy increases

• Both Kinetic and Potential energy

• Examples: PE= matches lighting & KE= heater

Chemical energy

• energy stored in chemical bonds

• when bonds break, released energy can do work

• all chemical compounds include fuel

• Potential Energy

• Example: gasoline or coal

Electrical Energy

• energy associated with electric charge

• movement of electrons

• can exert forces that do work

• Both Kinetic and Potential energy

• Examples: PE= charging a wire & KE= battery

Electromagnetic energy

• Energy of vibration of electrically charged particles

• Form of energy that can travel through an empty space

• Kinetic energy

• Examples: x-rays or light

Nuclear energy

• energy stored in nucleus of an atom; released when nucleus splits or combines

• Nuclear Fission: releases energy by splitting nuclei apart

• Nuclear Fusion: releases energy when less massive nuclei combine to form a bigger nuclei

• Potential Energy

• Example: nuclear power plant

Sound energy

• vibration of waves through materials

• Kinetic energy

• Example: any sound