Brainstorm Answer: Sailboats Listen in RealAudio Email Your Comments

Dave Thurlow, Host

 
Hi, I'm Dave Thurlow from the Mount Washington Observatory and this is The Weather Notebook. On a recent Brainstorm I gave you the following scenario. You're on a sailboat on a lake when the wind suddenly dies. For some reason, you have a generator and a really big fan on your boat. Will the fan help you get back to shore?

Aaron Hendricks from Ortenville, MI, a listener of affiliate station WFUM, thinks it can, but NOT by pointing the fan at the sails:

Isaac Newton

"It would not do any good to put the fan on the sailboat and point it toward the sails. Because the fan would be blowing air at the sails and pushing the mast forward, yes, but since the fan is on the boat, there would be the equal and opposite reaction of the fan acting like a giant propeller pulling the boat in the opposite direction. So, the boat would stand completely still."

That's right. Aaron remembered Newton's 3rd Law of Physics, which states 'for every action there is an equal and opposite reaction.' So if you shouldn't point the fan towards the sails, what should you do?

"To make it work, you could take the fan, turn it around and have it blow air at the back of the sailboat."

That's exactly it. Just think of those big airbpoats that cruise around the Everglades. Same principal.

So, if you're ever stuck on a lake with no wind, and you just happen to have a generator and a fan, point the fan backward...to go forward.

Tune in tomorrow for a brand new Weather Notebook Brainstorm. Our show is underwritten by Subaru with major support provided by the National Science Foundation.