Simple Machines Content Blast

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Simple MachinesContent Blast
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The Six Simple Machines

• Work, in physics, is a result of a force moving
  an object through a distance against a
  resistance. Work is always done by some agent,
  such as a person or a machine. This agent
  produces the force that causes the movement.

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Another Definition

• Force is a push or a pull. In your everyday life,
  you experience a variety of forces. You apply a
  force to a ball when you throw it up in the air.
  As the ball rises, the force of gravity slows it
  down. As the ball descends, gravity makes it fall
  more rapidly. When you catch the ball, it applies
  a downward force to your hands. But your hands
  apply an upward force to the ball to stop it.

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Six Simple Machines

• The six simple machines help us do work..
• The six simple machines help to add force to help
  move something.
• The six simple machines are
• lever, screw, pulley, wheel and axle,
  inclined plane, and wedge

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The Lever

• Lever, is one of the six simple machines for
  performing work. It consists of a rod or bar that
  rests and turns on a support called a fulcrum. A
  force of effort is applied at one end of the rod
  to lift a load placed at the other end. A lever
  can help lift a weight with less effort. Prying
  something loose with a crowbar is using a lever.
  Some machines, such as a catapult, use a lever to
  hurl objects.

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Three Classes of Levers

• First-class levers the fulcrum is in the
  middle like a seesaw,crowbar, or balance scale.
• Second-class levers- the load is in the middle
  like a wheel barrow, or a nutcracker.
• Third-class levers the effort is in the
  middle like a broom or a rake.

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First-class Lever

Effort
Load
Fulcrum
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Screw

• Screw is an inclined plane wrapped in a spiral
  around a shaft. The screw is one of the six
  simple machines developed in ancient times.

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Wedge

• Wedge is a device that has two or more sloping
  surfaces that taper either to a sharp edge or to
  a point. Wedges are used to split or pierce
  materials, and to adjust the positions of heavy
  objects. Knives, chisels, axes, pins, needles,
  and nails are wedges.

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Inclined Plane

• Inclined plane is a device used to raise heavy
  loads with relatively small forces. For example,
  pushing a load up a ramp onto a platform requires
  less force than lifting the load onto the
  platform.
• Ramps and steps are forms of inclined planes.

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Wheel and Axle

• Wheel and axle is a mechanical device used in
  lifting loads. It is one of the six simple
  machines developed in ancient times and ranks as
  one of the most important inventions in history.
  Sometimes teeth or cogs may be placed around the
  edge of the wheel, as in a cogwheel, or on the
  sprocket wheel of a bicycle.

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Pulleys

• Pulley is a wheel over which a rope or belt is
  passed for the purpose of transmitting energy and
  doing work.

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Different Kinds of Motion

• Objects may have straight, circular, or back and
  forth motions or movements.
• Objects vibrate like the strings on a guitar.
• Pushes or pulls can change the movement of an
  object.
• You can see movement or motion anywhere.