Unit 7: Potential and Kinetic Energy, Work and Power

What is potential energy?

Energy that is stored.

An object that is NOT moving has ______________________ energy.

Potential

What is kinetic energy?

Energy of motion.

An object that IS moving has __________________ energy.

Kinetic

A person riding a bike has __________________ energy.

Kinetic

What is work?

Work is when an object transfers energy to another object through force, and the affected object moves in the SAME DIRECTION of that force.

I push the wall and the wall doesn't move. Is work being done on the wall?

No.

I push my friend down and she falls to the floor. Is work being done on my friend?

Yes.

What do kinetic and potential energy have in common?

Both types of energy depend on motion or lack thereof. Both can be transferred from one type to the other. Both are measured in Joules.

This type of energy is depend on velocity (v).

Kinetic

This type of energy is dependent on height (h).

Potential

The unit for Work is

joules

The unit for Power is

Watts

Fw = mg is the formula for

weight measured in Newtons

The formula for Work =

force x distance

What is the formula for potential energy?

mass x gravitational acceleration x height

What is the formula for kinetic energy?

1/2 mass x velocity^2

When kinetic energy increases...

potential energy decreases

When potential energy increases...

Kinetic energy decreases

What is total energy?

the sum of kinetic energy + potential energy

The formula for height =

PE / mg

The formula for velocity =

the square root of (2KE / m)

As you go down a rollercoaster, the

PE decreases and KE increases

When height is 0 m, then

PE = 0 J AND KE = TE

When velocity is 0 m/s, then

PE = TE AND KE = 0 J