ENERGY
Energy Everything in the universe can be classified as either matter or energy. Matter is anything that has mass and takes up space. Energy is everything else like……
Energy Light Kinetic energy Sound Potential energy Chemical Electricity Nuclear energy Light Sound Chemical Thermal (heat)
Energy Energy is… The ability to cause change The ability to do work.
Energy The unit for energy is the joule. 1 joule = 1 kg x m2/s2
Kinetic Energy Kinetic energy (KE) is energy in the form of motion. The amount of kinetic energy an object has depends on its ___________ and _________ . KE = ½ mv2
Kinetic Energy Which has more kinetic energy? A bus traveling at 65 mph A car traveling at 65 mph Which has more kinetic energy? A bus traveling at 65 mph A bus traveling at 40 mph
Potential Energy Potential energy is ___________ energy. The amount of potential energy depends on its ____________ or ___________. Potential energy due to the object’s height above the earth’s surface is called ______________ .
Gravitational Potential Energy The formula for gravitational potential energy is… GPE = mgh
Gravitational Potential Energy Which has more GPE? A boy sitting in a tree 12’ above the ground A squirrel sitting in a tree 12’ above the ground. Which has more GPE? A squirrel sitting 12’ above the ground A squirrel sitting 30’ above the ground.
The Law of Conservation of Energy Energy cannot be created or destroyed only transformed from one form into another.
WORK The scientific definition of work is …. Work, like energy, is measured in ________ The formula for work is… W = F x d
WORK Two factors must be considered when deciding if work is being done Does the object move? What is the actual force applied?
He may expend energy when he pushes on the wall, but if it doesn’t move, NO WORK is performed on the wall!!!
WORK In which case, would more work be done? Lifting 1 book over your head or lifting 2 books over your head. Holding 2 books at shoulder level or lifting 2 books over your head. Holding a stack of books and walking them to the table or pushing a stack of books over the table.