work energypaas.psd202.org/documents/shollan1/1542236806.pdf · 2018-11-14 · kinetic potential...

ENERGY & WORK

Bill Nye Video WS - ENERGY

Energy makes things go!

Energy can be converted from one

form of energy to another!

Forms of Energy

▷ Kinetic▷ Potential▷ Chemical▷ Electrical▷ Thermal▷ Electromagnetic▷ Nuclear▷ Sound

Potential Energy

▷ Stored energy▷ Based on an

object’s position and mass

▷ PE = mgh▷ PE = weight*h

Kinetic Energy

▷ Moving energy▷ Amount of

kinetic energy depends on the object’s mass and speed

▷ KE = ½ mv2

Practice

A 15 kg bowling ball is sitting on a ledge 20 m high. What kind of energy does it have?

Calculate it!

Answer

A 15 kg bowling ball is sitting on a ledge 20 m high. What kind of energy does it have?

Potential

PE = (15 kg) (10 m/s2)(20 m)

PE = 3000 J

Practice

A 15 kg bowling ball is rolling down a hill at a speed of 4 m/s. What kind of energy does it have?

Calculate it!

Answer

A 15 kg bowling ball starts rolling down a hill at a speed of 4 m/s. What kind of energy does it have?

Kinetic

KE = ½ (15 kg)(4 m/s)2

KE = 120 J

Kinetic and Potential Energy WS

Conservation of Energy

Energy cannot be created or destroyed, only transformed from one form to another…

SO the total energy of a closed system should remain constant!

Total Mechanical Energy

The relationship between kinetic and potential energy…

TME = PE + KE

Roller Coaster Project