GEARS:

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GEARS
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Gears

• Gears are teeth on a wheel and axel.
• The teeth of one gear fit between the teeth
  of another gear.

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Gears

• When one gear turns, the other can be made to
  turn faster, slower or in another direction.
• The gears on a clock allow the three hands to
  move around the face of the clock at different
  speeds.

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Gears
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Gears

• The wheel that moved first is called the driving
  gear.
• Usually the driving gear is moved by a person or
  a motor.

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Gears

• The wheel that is moved by the driving gear is
  called the driven gear.

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Gears

• Different sizes and arrangements of gears are
  used to make wheels turn faster, slower or in
  different directions.

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Gears

• A large driving gear makes a small driven gear
  move faster, but in the opposite direction.
• Hand driver drills use this combination of gears
  to make them spin quickly.

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Gears

• A small driving gear makes a large driven gear
  move slower but in the opposite direction.
• This arrangement acts as a force multiplier.
• It is used to move large loads with a small
  effort.

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Gears

• Pairs of gears the same size change the direction
  of turning without changing the speed.

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Gears

• Bevel gears are gears that are at right angles to
  each other and can change vertical motion into
  horizontal motion.

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Gears

• Rack and pinion gears consist of a flat row of
  teeth called a rack and a circular gear wheel.