Simple Machines Chapter 6

“The perplexity of life arises from there being too many interesting things in us to be interested properly in any of them” -G.K. Chesterton

Read p.88-89

Machine a device that changes the amount or direction of the force needed for work 6 main types

Inclined Plane a simple machine that allows us to raise objects little by little instead of all at once

Screw A special type of inclined plane that can convert a rotational movement into a vertical movement A screw is a spiral inclined plane

Wedge a simple machine made out of two inclined planes placed back to back

Lever A long board or rod that rotates around a fulcrum Fulcrum: a sturdy object or surface that the board rotates around 3 types of levers

First Class Lever A lever in which the fulcrum is between the force and the load

Second Class Lever Levers in which the load is between the force and the fulcrum Increase force, does not change direction

Third Class Lever A lever in which the force is in the middle of the fulcrum and the load Multiply distance

What type of lever is this?

Wheels Friction: the drag when objects move across each other Rolling wheel: decreases the amount of friction (drag) involved in work

Wheel and Axle A simple machine made of a wheel firmly attached to a rod (axle) Force is applied to the wheel

Reverse Wheel and Axle The force is applied to the axle

Pulley A wheel in a frame Can change the direction of the force or the amount of force

4 types of pulleys Changes the direction & decreases amount of force Changes direction of force Decreases the amount of force