P. Sci.

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P. Sci.

• Motion Forces Newtons Laws of Motion

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Force
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• What causes an objects position to change. A
  push or a pull.

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Force cont.

• Net force the combination of all forces acting
  on an object.
• If 0 (they cancel out) the object does not move
  or it moves at a constant velocity. (balanced
  force)

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Force cont.

• If not 0 the object will move in the direction of
  the net force. (unbalanced force)
• If there is a net force, acceleration will take
  place. Either the object will change direction
  or change speed.

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Newtons 1st Law
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• An object at rest remains at rest, an object in
  motion remains in motion unless acted on by an
• unbalanced force.

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1st Law AKA Law of Inertia
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• Inertia the tendency for an object to resist a
  change in motion.

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Newtons 2nd Law

• The unbalanced force acting on an object equals
  the objects mass times its acceleration

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2nd Law AKAF ma
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• Force is measured in Newtons (N)
• 1N 1kg x m/s2
• Ten times as much.

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Newtons 3rd Law
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• For every action force, there is an equal and
  opposite reaction force.

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AKA Law of Action/ReactionNewtons 3rd Law

• When you sit in your chair, your body exerts a
  downward force on the chair and the chair exerts
  an upward force on your body.

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• Consider the propulsion of a fish through the
  water. A fish uses its fins to push water
  backwards. In turn, the water reacts by pushing
  the fish forwards, propelling the fish through
  the water.
• The size of the force on the water equals the
  size of the force on the fish the direction of
  the force on the water (backwards) is opposite
  the direction of the force on the fish
  (forwards).

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Momentum
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• Property of moving objects resulting from its
  mass and velocity.
• Comes from Newtons Third Law

Momentum (p) mass x velocity pm x v