Simple Machines

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Simple Machines

• Simple Machines are tools that make work easier
  and have few or no moving parts. Most simple
  machines make work easier by trading the amount
  of force used with distance.
• Simple machines require energy to do work.
• We often use simple machines to move loads. A
  load is the object that you are moving such as a
  box of paper.

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Types of Simple Machines

• The 6 types of simple machines are
• The Pulley
• Lever
• Wedge
• Wheel
• Inclined Plane
• Screw

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Pulley

• A pulley uses grooved wheels and a rope to raise,
  lower, or move a load. Many windows are raised
  and lowered using pulleys.
• Pulleys make a change in the direction of the
  force that is applied to an object. A pulley
  allows you to pull sideways to lift an object.

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Lever

• A lever is a stiff bar that rests on a middle
  support. A lever, such as a see-saw, can be used
  to lift or move loads.
• A lever trades force for distance. The longer the
  effort arm of a lever, the less force you will
  need to lift the load.

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Wedge

• A wedge has at least one slanted side that ends
  in a sharp edge. An axe blade is a wedge that
  cuts material apart.
• A wedge reduces the amount of force you must use
  to split objects.

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Wheel and Axle

• A wheel with a rod through its center lifts or
  moves loads. The rod is called an axle. Cars and
  trucks have four wheels and four axles.
• A wheel reduces the amount of friction an object
  must push against.

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Inclined Plane

• An inclined plane is a slanted surface. It is
  much easier to move an object up an inclined
  plane than straight up.
• An inclined plane trades force for distance. It
  takes less force to walk up a ramp, but you must
  walk farther than going up stairs.

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Screw

• A screw is an inclined plane that is wrapped
  around a pole. Screws hold things together and
  can be used to lift materials.
• A screw trades force for distance. It takes many
  spins of a screwdriver to put a screw in a board.
  Once it is in the board it would take a great
  force to remove it.

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Simple Machines are used to solve problems.

• People use simple machines everyday to help them
  solve problems.
• Screws are used in construction and help hold
  objects together.
• Levers help lift heavy objects.
• Wheels help move objects around.
• Inclined planes help move objects to higher
  places easier such as ramps.

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Questions You May See On the EOG

• Which kind of tool makes work easier and has few
  or no moving parts?
• A. a complex machine
• B. a simple machine
• C. an axle
• D. a pulley
• What is an inclined plane that is wrapped around
  a pole also known as?
• A. Wedge
• B. Pulley
• C. Wheel
• D. Screw