Study Guide for Simple Machines

Wedges

a pair of inclined planes wrapped around a cylinder.

Screws

an inclined plane wrapped around a cylinder.

Mechanical Advantage

the number of times the machine multiplies force.

Mechanical Efficiency

work output /work input +100 (measured as percentage %)

Mechanical Advantage

output force (N)/input force (N)

Work

Is done when a force causes an object to move in the direction of the force

Simple Machine Does What

make work easier; NOT LESS WORK

Machine

a device that makes work easier by changing the size or direction of the force

Work Input

the amount of work you put into the machine

Work Output

the amount of work done by the machine

Mechanical Advantage

the number of times the machine multiplies force

Mechanical Efficiency

work output/work input +100 (measured as percentage %)

1st Class Lever

the fulcrum is between the input force and output force

2nd Class Lever

fulcrum at one end with input force at the other end and output force in between

3rd Class Lever

the input force is between the fulcrum and the output force

Pulleys

a simple machine that has a grooved wheel and a rope or cable

Wheel and Axle

simple machine consisting of two circular objects of two different sizes.

Incline Plane

a simple machine that is a straight slanted surface (ramp)

Screws

an inclined plane wrapped around a cylinder

Lever Equation

Distance from Input Force to Fulcrum/Distance from Output Force to Fulcrum

Incline Plane Equation

Length of ramp/ Height of ramp

Wheel and Axle Equation

Radius of the wheel / Radius of the axle

Pulley Equation

If going down, Count # of pulleys ; If going up count the number of ropes

Wedge Equation

Length of the wedge / the thickest part of the wedge

Compound Machine

two or more machines combined into one