Six Simple Machines have many uses.
· There are six simple machines:
2. Wheel and Axle
4. Inclined Plane
· Simple Machines- Six machines from which all other machines are based.
· A solid bar that rotates, or turns, around a fixed point.
· That fixed point is called a fulcrum.
· Multiplies the input force.
· Can change direction of the input force.
· If you apply a force downward on one end of the lever, the other end can lift a load.
There are three classes of levers.
1. First-Class Lever- The fulcrum is between the input and output forces.
2. Second-Class Lever- The output force is in between the input force and the fulcrum.
3. Third-Class Lever- The input force is located between the output force and the fulcrum.
WHEEL AND AXLE
· Made of a wheel attached to a shaft, or axle.
· Wheels of bikes and cars are attached to axles.
· The axle acts like a fulcrum.
· EXAMPLES: SCREWDRIVERS,STEERING WHEELS, DOORKNOBS
· You apply a force to turn the axle or wheel.
· Your input force is transferred.
· Since the axle is smaller, the output force acts over a shorter distance than the input force.
· A wheel with a grooved rim and a rope or cable that rides in the groove.
· As you pull the rope, the wheel turns.
· A fixed pulley is attached to something that holds it steady.
-Changes the direction of the force.
-Does not reduce the force needed to lift the load.
-distance pulled = distance lifted
· A movable pulley setup is when the rope is fixed at one end but the wheel can move.
· A block and tackle system is a combination of both. Used on very heavy objects.
· A simple machine that is a sloping surface.
· The less steep the inclined plane, the less force you need to push an object on an inclined plane.
· This is because the steeper the plane, the less the plane supports the weight of the object.
· Simple machine with a thick end and a thin end.
· Used to cut, split, or pierce objects, or to hold objects together.
· EXAMPLES: DOORSTOPS, CHISELS, ICE SCRAPERS, AXE BLADES
· A chisel breaks things apart,while a doorstop holds things
· An inclined plane wrapped around a cylinder or cone to form a spiral.
· Can be used to raise and lower weights as well as to fasten objects.
· As the screw is turned, the threads act like wedges, exerting an output force on the wood.
· SIX SIMPLE MACHINES HAVE MANY USES
· SIX SIMPLE MACHINES ARE: LEVER, WHEEL AND AXLE, PULLEY, INCLINED PLANE, WEDGE, SCREW
· THREE CLASSES OF LEVERS (1ST, 2ND, 3RD CLASS)
FOR ANIMATIONS OF THE 6 SIMPLE MACHINES!