Energy Transformations

Energy

Ability to do Work or cause Change

Energy comes in many Forms

• Potential, In Storage waiting to be used– Chemical– Mechanical: Tension in a spring or rubber band– Nuclear– Gravitational– Electrical– Human: 8th graders at Butler Middle School

• Kinetic, In use, involves motion – Radiant: Electromagnetic, light, x-rays– Thermal: Heat– Motion– Sound

Weight pushes down into roadRoad reacts by pushing up on car

No Forces are parallel to the road

With breaks off, car will Not move, unlesssomething pushes, pulls or starts it.

Parked Level Car, Newton’s 1st and 3rd Laws

2 forces are present, parallel to road

Force to left is pushing car forwardForce to right is air resistance and friction

Chemical Energy in tank is converted to Kinetic energy of themoving car

Accelerating Car, All 3 of Newton’s Laws

Parked Car on a Hill

Weight is equivalent to parallel and perpendicular forces

Brake

With break on, Car has all Potential Energy from gravity

If Break is turned off, Car will move, PE converts to Kinetic Energy

Today’s Experiment

If truck is just coasting, is this animation an accurate model of the truck’s motion?

Today’s ExperimentAll PE

All KEmax speed Stop

D

SlowingHeight

What will effect distance D ?

What happens to KE as truck slows down?What keeps truck moving at bottom of ramp?

What if we could eliminate all friction and air resistance?