Simple Machines There are 6 basic types

1 - INCLINED PLANE An inclined plane is a flat, sloped surface How it works: *It increases distance and decreases input force Mechanical Advantage: Ideal mechanical advantage = length of incline height of incline *the longer the incline the greater the mechanical advantage

2 - WEDGE A wedge is a device that is thick at one end and tapers to a thin edge at the other end How it works: * you move the inclined plane itself into an object and the output force is at a 90 degree angle from its input force Mechanical Advantage: Ideal mechanical advantage = length of wedge width of wedge *the longer and thinner the wedge, the greater the mechanical advantage*

3 - SCREW A screw is an inclined plane wrapped around a cylinder. How it works: * When you turn a screw, the threads act like an inclined plane to increase the distance…so it decreases the amount of input force needed. Mechanical Advantage: Ideal mechanical advantage = length around the threads length of the screw *the closer the threads are, the greater the mechanical advantage*

4 - LEVERS A lever is a rigid bar that is free to pivot, or rotate, on a fixed point called the fulcrum. How it works: * It uses a fulcrum to maximize output force or output distance. Mechanical Advantage: Ideal mechanical = distance from fulcrum to input force advantage distance from fulcrum to output force

Types of Levers 1 - First-Class Lever: The fulcrum is in the MIDDLE! It changes direction of the force Can increase force or distance The closer the fulcrum is to the input force, the greater the distance

2 - Second-Class Lever: The OUTPUT FORCE (load) is in the MIDDLE! It increases force It does NOT change the direction of the force

3 - Third-Class Lever: The INPUT FORCE (effort) is in the MIDDLE! It increases DIRECTION It does NOT change the direction of the force

More LEVER Examples:

5 – WHEEL AND AXLE A wheel and axle are two circular objects fastened together that rotate about a common axis. The larger radius is the wheel and the smaller radius is the axle. How it works: * The wheel increases your output force by applying a greater distance to your input force. It increases your force. Mechanical Advantage: Ideal mechanical = radius of wheel advantage radius of axle

6 – PULLEY A pulley is made of a grooved wheel with a rope or cable wrapped around it. How it works: * The input work is the pulling of the rope and the output force pulls up on the object you want to move. It increases the effect of the input force and changes direction. Mechanical Advantage: Ideal mechanical = the # of sections that Advantage support the object

Types of pulleys Does not change the force, only the direction of the force. MA = 1 Increases the amount of force, but not the direction. MA = 2 Made up of fixed and moveable pulleys.