Warmup:

1
Warm-up

• What is friction?
• Is friction always the same for a given object?
  Why or why not?

2
Newtons Laws in Action

• Lets turn em in!!

3
Elevator Problems Worksheet

• Any Questions?

4
Friction Notes

• The friction force is the force exerted by a
  surface as an object moves across it or attempts
  to move across it.
• The friction force opposes the motion of the
  object.
• Friction results from intermolecular attractive
  forces between molecules of different surfaces.
• Friction depends upon the nature of the two
  surfaces and how firmly they are pressed
  together.

5
Friction Notes
6
Friction Notes
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Air Resistance

• Air resistance is a special type of frictional
  force which acts upon objects as they travel
  through the air.
• Depends on speed and mass.
• When FG and FAR are equal (balanced) there is no
  more acceleration, which means that terminal
  velocity has been reached.

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Air Resistance
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Air Resistance
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Assignment

• Read textbook pages 63 70 and add to your
  notes.
• Begin Friction and Air Resistance WS
• Finish for Homework