Simple Machines

Inclined Plane

• An inclined plane is a slope or a ramp
• As the slope increases the more force is required to be use

Wedge

• A wedge is two inclined planes back to back
• Both a wedge and an inclined plane have a sloping surface

Screw

• A screw is an inclined plane wrapped around a cylinder
• Both a screw and an inclined plane us force in a direction different than the load

Wheel and Axle

• A wheel and axle is a circular lever, whose fulcrum (pivot point is an axle
• A wheel and axle allows the lever to rotate through 360 degrees instead of the limited teeter-totter application

Lever

• A lever is a bar that turns on a point
• There three parts to a lever: the first class lever, the second class lever, and the third class lever

Lever cont.

• First class lever: the fulcrum is located in the middle. 2 examples scissors and a crowbar
• Second class lever: the load is located in the middle. 2 examples are wheel barrow and a bottle opener
• Third class lever: effort is located in the middle, 2 examples are a fishing pole and a tennis racket

Pulley

• A pulley is a circular lever, put it rotates freely on the axle
• Three different types of pulleys are a fixed pulley, a movable pulley, and a combined pulley

Work

• Work is when something is moved
• Formula is Force times Distance
• Machines change the amount of force needed to do work.

Mechanical Advantages

• Mechanical advantage is the ratio of an output force to input force
• MA measures mechanical advantages
• Actual MA has friction, ideal doesn't.
• Actual MA is always less ideal that ideal MA because of friction