Hollywood movies often slightly bend the laws of physics (as in The Matrix), the laws of biology (as in X-Men), or the laws of meteorology (as in Twister). However, it's the rare movie that hits the trifecta of wildly violating all three disciplines at once. In honor of the recent direct-to-tv movie Sharknado, which is, as the title implies, about great white sharks being hurled onto the California coastline by a tornado, we give you a little flying shark physics:

What is the wind speed in m/s required to keep a great white shark suspended in midair during a summer day on the California beach?

Details and assumptions

• Model the shark as a horizontal cylinder $6~\mbox{m}$ long and $1~\mbox{m}$ in diameter.
• The air is at a pressure of $1~\mbox{atm}$ and a temperature of $30^\circ\mbox{C}$.
• The density of the shark is that of water, $1000~\mbox{kg/m}^3$.
• Assume that the wind gust that keeps the shark suspended is blowing straight upwards, and that the air molecules bounce off the shark elastically.
• The acceleration of gravity is $-9.8~\mbox{m/s}^2$.
• $m_a$, the molar mass of air, is $29~\mbox{g/mol}$.
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