DAILY QUESTION January 27, Name the six simple machines.

Agenda1/27/09 Daily Question Hand-in: 12-1 Wksht Chapter 12 Section 2 Notes Assignments: 1. Finish your Simple Machine Poster due 1/28

Simple Machines The basis for all other forms of machines There are 6 basic types from 2 families: 1.Simple lever 2.PulleyLEVER 3.Wheel and AxelFAMILY 4.Simple Inclined Plane 5.WedgeINCLINED PLANE 6.ScrewFAMILY

Simple Levers All levers have a rigid arm that turns around a point called a fulcrum Force is transferred from one part of the arm to another

Simple Levers There are 3 classes that depend on location of fulcrum and the forces. –First class – fulcrum in the middle Claw Hammer, teeter-totter –Second class – fulcrum on far side, input on end Wheelbarrow, bottle opener –Third class – fulcrum on far side, input in the middle Forearm, tweezers

Pulleys Like a lever, the point in the middle of the pulley is like the fulcrum of a lever and the rest of the pulley is like the rigid arm of a first class lever –Flag pole, Sail boat

Wheel and Axle Made of a lever (or pulley), the wheel, connected to a shaft, the axle. Small input force is multiplied to become a large output force –Steering Wheels, screwdrivers

Simple Inclined Planes Turns a small input force into a large output force by spreading the work out over a large distance –Ramps

Wedge Functions like two inclined planes back to back Turns a single downward force into two forces directed out the sides –Nails, Ax Blade

Screw A screw is an inclined plane wrapped around a cylinder Requires a small force over a larger distance –Jar lids, spiral staircases

Compound Machines A machine that combines two or more simple machines –Scissors, Car Jacks