1. Energy Conversion and Conservation

2. Review - Work
Work is done when a force acts on an object in the direction the object moves.
Work = Force x Distance
W = F x D
The joule (J) is the SI unit of work.

3. Review - Power Power is the rate of doing work. Power = Work / Time
P = W/t
The SI unit of power is the watt (W)

4. Review - Energy Kinetic potential
Work causes a change in the energy of a system.
The two main types of energy are:
Kinetic
potential

5. Review – Kinetic Energy
Kinetic energy depends on motion and is measured in joules (J).
KE = ½ mv2
v = velocity

6. Review – Potential Energy
Gravitational Potential Energy depends on height and is measured in joules (J).
PE = mgh
h = height
g = acceleration due to gravity 9.8m/s2

7. Energy Conversion Energy can be converted from one form to another.
The process of changing energy from one form to another is energy conversion.
EX: Rubbing hands – kinetic energy to thermal energy.

8. Conservation of Energy
When energy changes from one form to another, the total energy remains unchanged.
The law of conservation of energy states that energy cannot be created or destroyed.

9. Energy Conversions
The gravitational potential energy of an object is converted to the kinetic energy of motion as the object falls.
EX: sky diving
The kinetic energy of motion is converted to gravitational potential energy when an object is gaining height.
EX: pole vaulting

10. Energy Conversion in a Pendulum

11. Energy Conversion
Your beginning energy must equal your ending energy. This allows us to say that:
(KE + PE)beginning = (KE + PE)end
Which means you can set kinetic energy equal to potential energy.