Upload
tiffany-dorsey
View
224
Download
0
Tags:
Embed Size (px)
Citation preview
EnergyEnergy – the ability to do work
the ability to cause changemeasured in joulessymbol:
[as in.. E = mc2]
E
EnergyTwo descriptions:
Potential Energystored energy
[due to position or condition]Kinetic Energy
energy of motion / released energy
Potential EnergyThree Types:Elastic PE
energy stored by something that can stretch or compress [rubber band or spring]
Potential EnergyThree Types:Gravitational PE
energy stored because of position above earth’s surface
Potential EnergyGravitational PE:
PEgravitational = mass * accel. of gravity * height
PEgravitational = m g h
Remember, g = 9.8 m/s2
Potential EnergyGravitational PE:
so…what’s the unit?PEgravitational = m g h
PEgravitational = kg * (m/s2) * m
PEgravitational = N * m
PEgravitational = Joules
Kinetic EnergyKinetic Energy – released by an object by its
motiondepends on the mass and speed of an
objectKE = ½ * mass * velocity2
KE = ½ m v2
Kinetic EnergyKinetic Energy – released by an object by its
motionSo…what’s the unit?
KE = ½ * mass * velocity2
KE = (kg) * (m2/s2)KE = Joules