Spectacular Science

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Spectacular Science
Spectacular Science

• Presentation by Daniel Riedinger
• Teacher Reseda HS Police Magnet

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Friction

• What is it
• Opposes motion
• empirical laws of friction first investigated
  more than five hundred years ago by Leonardo da
  Vinci

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Types of Friction

• Sliding Friction friction produced when two
  solid objects slide over each other.
• Rolling Friction friction produced when an
  object rolls over a surface.
• Fluid Friction friction produced when an object
  moves through a fluid.

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Is Friction a Good Thing or a Bad Thing?
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What Affects Friction

• Surface type and weight
• Force from friction/weight of object
• A constant number
• f / N µ the coefficient of friction
• f µ N
• What about surface area?
• Friction is independent of surface area

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Tornadoes

• Whirling funnel shaped cyclone
• Common on the great plains during spring
• Up to 300 mph winds

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Tornadoes

• Tornados are the smallest, most violent, and
  shortest lived severe storm.
• When a thunderstorm encounters high altitude,
  horizontal winds, a tornado can be formed.
• These winds can cause the rising air in the
  thunderstorm to start rotating.
• A narrow funnel shaped, rapidly spinning
  extension may develop in the cloud.

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• Tornados generally cover a path of about 100m
  wide, destroying everything in their path.
• The tremendous speeds of the winds in a tornado
  are responsible for the destruction they cause.
• The falling of debris when a home is destroyed or
  being struck by flying objects causes most deaths
  and injuries.
• It is very important to find cover in a low
  place.

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Worst Tornado

• March 18, 1925
• Started in Missouri, ended in Indiana
• Forward speed was a record setting 73mph
• For over 100 miles, the path was about three
  quarters of a mile wide
• 2027 injured, 695 dead