Pebble Skipping

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Pebble Skipping

• TMF 2004
• Gymnázium Eliky Krásnohorské

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Pebble skipping
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What is it?

• Pebble
• smaller flat oval stone
• Throw
• approximately parallel with water level
• sufficient speed and rotation maximal kinetic
  energy

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Scheme of a motion
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Scheme of forces
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Rotation (spin)

• when pebble strike water level, braking force
  doesnt react in gravity centre
• stone would lose right slope to water level
• rotating stone is as flywheel

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Record

• Jerdone Coleman-McGhee,
• 38 jumps
• throwed under angle 20º with speed over 40km / h
• at least 840 RPM