Energy
Types of Energy
Potential energy Kinetic energy
The ability to do work Shown by:
– Application of force – Movement of something by that force.
Force
Push or pull
more • More acceleration = _____ force more • More mass = _____ force
Force = mass X acceleration
F = ma
Energy
Work = force x distance (W = F x d) Measured in Joules:
–N (unit of force) combined with with M (unit of distance).
Potential Energy
Stored energy:
fuel –Energy that can be burned ____ a battery –Chemical energy stored in _______ –Energy stored in food as ______ sugars –Energy from height above the earth’s surface ________________ gravitational energy
Gravitational Energy
• Due to the attractive gravitational force between all objects in the universe • Near Earth’s surface the force due to gravity is 9.8 m/s/s
Gravitational Energy
W=Fxd gPE = mgh m = mass of the object g = gravitational force 9.8 m/s/s h = height above the surface of the earth
Kinetic Energy
Energy due to motion depends on:
mass – _____ of the object speed – ______ of the object
More connected to speed than mass: KE = ½ mv2
m = mass v = speed
Conservation of Energy
• Energy can’t be created or destroyed • Can change from one form to another • Examples:
– Fuel burning makes ____ heat light – Battery makes ____ – Use gravity to make ______ motion