Energy & Types of Energy

What is Energy?

• The ability to do work

• Each time work is done, energy is transferred from one object to another

• Work & energy are so closely related that they are both expressed in Joules (J)

What is Kinetic Energy?

• Kinetic Energy = ENERGY OF MOTION

• All moving objects have kinetic energy

• Objects with kinetic energy can do work

Example of Kinetic Energy

•Example: A hammer moves & hits a nail The downward swinging force pushes the nail down = work being done

How Do You Calculate Kinetic Energy?

• KE = mv2

**Velocity has a HUGE affect on kinetic energy

m=massv=velocity

What is Potential Energy?

• Potential Energy = STORED ENERGY

• This is the energy an object has because of position or shape.

Example of Potential Energy

• Example: Work is done on a bow to stretch it out and change its shape

How Do You Calculate Potential Energy?

• Gravitational potential energy depends on an object’s weight & height above the Earth’s surface.

• PE = weight x height

What is Mechanical Energy & How Do You Calculate It?

• Total energy of motion & position

• ME = KE + PE

Example of Mechanical Energy