Physics of balls

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Physics of balls

• Adam Szalai
• Jurisich Miklós High School
• KOSZEG

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I love sport,

• I like to play football,

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And I also love sciences

• I love basketball,

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The ball

• Size, shape, mass, material, elasticity all
  depending on the sport
• Soccer, basketball, volleyball, handball,
  football, baseball, la-cross, golf, table tennis,
  tennis, bowling, snooker etc.

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What happens to the ball?

• Collision
• Starting energy is given to the ball
• With rackets, hands, foot, stick, cue
• Collision is more or less elastic
• Conservation of momentum can be used during the
  collision (angles!)

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Deformation

• Can be observed in low-speed movies
• Can be observed in case of slow motion (bubbles)
• Volume is approximartely the same
• Smaller surface bigger surface

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Motion of the ball

• Rolling on the surface
• Slows down and stops b/c of friction
• (E.g. golf bowling etc.)
• Depends on the friction

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Motion in the air

• Theoretically projectile. The path is parabola
• Vertically uniformly accelerates (g)
• Horizontally Uniform motion
• In practice air resistance affects the path

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Why does the path bend?

• Air sticks to the spinning objects
• As spinning body moves, the relative speed is
  different, pressure is different (Bernoulli law)

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Speed pressure
p Vrel
p Vrel
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Magnus effect

• In sport - bent path of the balls
• In traffic - on a two-lane road two oppositely
  moving cars
• Helicopters
• Etc.

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Be careful with it take advantage of it, you
might become famous