FORCES

1
FORCES

• CH. 2

2
What is a Force?

• Def a push or a pull
• Measured in Newtons
• Kg ? m/s2
• Balanced Force an equal but opposite force
  acting on an object.
• Net force is 0
• Does not cause a change in motion
• Unbalanced force
• causes a change in motion
• Newtons 3 Laws of Motion
• Law of Inertia
• F MA
• Action- Reaction

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Examples of Forces

• Friction force that opposes motion
• Sliding, rolling or fluid (gas or liquid)
• Air Resistance fluid friction of objects moving
  through air
• Lubricant a fluid that reduces friction
• Static Friction friction between two objects
  that are not moving
• Friction is good and bad
• Good
• Bad

4
Examples of Forces

• Gravity pulling force between objects
• Law of universal gravitation all objects in the
  universe exert a gravitational pull on all other
  objects in the universe
• Size of the gravitational pull depends on mass
  and distance
• larger the mass greater the force of gravity
• Greater the distance between the objects
  gravity is less

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Examples of Forces

• Acceleration due to Gravity the rate at which
  falling objects accelerate
• Same for all objects, regardless of mass, size or
  shape
• This is without any other forces (air resistance)
• Earth 9.8 m/s2 Moon 1.6 m/s2
• Terminal Velocity fastest an object can fall
  because of air resistance
• Air resistance Force of Gravity
• Weight measure of the force of gravity on an
  object
• Mass X acc. Due to gravity