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Course 30189: Maths21A Summer 2010
Multivariable Calculus
Office: SciCtr 434


This is a problem related to work line integrals: is it possible to build a windmill car which drives against the wind? The answer is yes. One sees this best by going to the extreme. Take a windmill and put it on wheels. The energy which the windmill generates is transformed into motion. Imagine the windmill to have to turn a few dozen times until the wheel of the car turns ones.

It is counterintuitive that one can use the wind to drive against the wind, but every sailboat does that too. On the picture you see such a car.

Here is a windmill car on Video.

Please send questions and comments to maths21a@fas.harvard.edu
Maths21A | Oliver Knill | Summer 2010 | Summer school | Department of Mathematics | Faculty of Art and Sciences | Harvard University QR code of this page