# Physics Norquist Chp 9

## 23 terms · Gawd I HATE physics. :P

### Work (formula)

W = fd (force x distance)

### Work (description)

When a force acts on an object and the object moves in the direction of the force

### Energy

Property of an object or system that enables it to do work

### Mechanical Energy

Energy due to the position of something/movement of something

### Potential Energy (formula)

PE = mgh (mass x gravity x height)

### Potential Energy (description)

Energy that is stored and held for readiness

### Elastic PE

Energy that is stored by means of it being stretched or compressed

### Chemical PE

Energy that is a available when the positions of electric charges within and between molecules are altered

### Gravitational PE (description)

Energy that is stored against Earth's gravity

### Gravitational PE (formula)

GPE = weight x height

### Kinetic Energy (formula)

KE = 1/2mv2 (1/2 the mass x velocity to the 2nd power)

### Kinetic Energy (description)

Energy in motion
KE of a moving object = the work required to bring it to its speed

### Work-Energy Theorem (formula)

W = delta KE (delta = change in)

### Work-Energy Theorem (description)

States that whenever work is being done, energy changes

### Law of Conservation of Energy

States that energy CANNOT be created or destroyed, only transformed. But the total NEVER changes

### Machine

Used to multiply or change the direction of forces; transfers and transforms energy

### Lever

A simple machine made of bar that turns a fixed point

### Fulcrum

Pivot Point

MA = force out/force in OR MA = distance w/ a machine/distance w/o machine

Ratio of the output and input force

### pulley

A kind of lever that can be used to change the direction of force

### Efficiency (description)

Ratio of useful work out to total work in

### Efficiency (formula)

Eff = useful work out/total work in

Create Set