Physics of Surfing

1
Physics of Surfing

• By Katy Stennett and Josh Leggett

2
The Surfboard

• Ancient longboards were often heavy and not
  easily maneuvered.
• The boards were also very tall and made out of
  low-density wood.
• Currently, the boards are shorter and lighter.
• Everything about a surfboard has to do with
  physics.
• The shape of the board, nose, tail, and fin all
  have to agree with laws of physics.

3
Tides Currents

• Tides are created by the attracting forces of the
  sun or moon and inertia.
• A surfer follows a tide out to sea to get in
  position to catch a breaking wave.

• Wind and gravity are the two main causes of a
  current.
• The current can be determined by either direct or
  indirect winds form a storm.
• If a current is heading north, a surfer should
  enter a wave from its southern end.

4
Velocity Equations

• Surface Gravity Waves
• C gT/2LL
• Where C Wave Speed
• G Acceleration Due to Gravity
• T Wave Period
• L Wave Length

• Shallow Water Waves
• C gD
• Where C Wave Speed
• G Acceleration
• D Depth

5
Science of Waves

• Waves are created by wind and gravity.
• The largest waves occur during storms like
  hurricanes.
• The largest wave ever recorded was in 1993 in the
  south pacific. The wave reached 112 feet high.
  The U.S.S. Rampano measured it.
• Small waves move slower than large one.
• Surfers prefer the larger waves as long as the
  they can keep in front of the whitewater.

6
Balance

• Balance is one the most important items to
  surfing.
• The stringer runs down the middle of the board.
  It is only about 1/8 thick and provides strength
  and weight along the middle of the board.
• The center of gravity is toward the back of the
  board on the stringer.This point acts as an axis.

7
Floating Equations

• Pdensity of water
• Fmaximum buoyancy force
• Hamount of thickness of surfboard that is
  submerged
• pdensity of surfboard
• wweight of surfboard
• hthickness of surfboard
• Aarea of surfboard
• Wsweight of surfer
• F-w-Ws,wf-Ws,pghAPgHA-mg,pPH/h-m/hA