SIMPLE MACHINES

LEVER

• A lever is a bar that is free to pivoy,or turn, about a fixed point.
• Levers are used to pry many things apart.
• There are three diffrent types of levers .
• The differentces are based upon the positions of the effort force,resistsnce force,and fulcrum
• They also are arranged by first class, second class, and third class.

PULLEYS

• A pulley is a grooved wheel with a rope, chain, or cable running along the grove.
• A fixed pulley is a modified first-class lever.
• The axle of the pulley acts as the fulcrum.
• The two sides of the pulley are the effort arm and resistance arm.
• A pulley can multiply the effirt force, but all pulleys can change the direction of the effort force.

WHEEL AND AXLE

• A wheel and axle is a machine consisting of two wheels of different sizes that rotate together.
• Both parts of a wheel and axel move in ac circle.
• The smaller wheel, the axel, usually exerts the resistance force.
• The handle on a pencile sharpener is an example of a wheel and axel.
• The wheel and axle is another form of a lever,

INCLINED PLANES

• A sloping surface, that reduces the amount of force required to do work is an inclined plane.
• A ramp is an example if an inclined plane.
• Inclined planes are more useful to people in wheel chairs.
• IMA- ideal mechanical advantage = length of slope/height of slope.
• BY using a ramp you will not hurt yourself as much.

SCREW

• A screw is an inclined plane wrapped in a spiral around cylindrical post.
• While looking closely at a screw you will find threads from tiny ramp thta runs upward from its tip.
• When you turn a screw, the threads seem to pull the screw into the wood.
• The wood seems to slide up the inclined plane.
• A lid is a another example of a screw.

WEDGES

• A wedge is an inclined plane with one or two sloping sides.
• Wedge is also a simple machine where the inclined plane moves through an object or material.
• A knife is an example of a wedge.
• When wedges are being used it moves through an object in a downward motion, the force is changed to a horizontal motion, forcing the apole apart.

COMPOUND MACHINES