(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

The Michelson-Morley experiment for a real wind (This is taken from Resnick and Halliday, Basic Concepts in Relativity (MacMillan, New York, 1992).

A pilot plans to fly due east from A to B and back again. If u is her airspeed (speed of plane with respect to the air) and if l is the distance between A and B, it is clear that her roundtrip time t — if there is no wind — will be 2l/u.

a) Suppose, however, that a steady wind of speed v blows from the west. What will the round trip travel time now be, expressed in terms of l, u, and v?

b) If the wind is from the south, explain how you would find the expected roundtrip travel time, again as a function of l, u, and v. (If you can find the travel time, do it!)

c) Note that these two travel times are not equal. Should they be? Did you make a mistake?

d) In the Michelson-Morley experiment, however, the experiment seems to show that (for arms of equal length) the travel times (and thus path lengths) for light are equal; otherwise these experimenters would have found a pattern shift when they rotated their experiment. What is the essential difference between these two situations?

2. Relevant equations

Distance = speed x time.

3. The attempt at a solution

I = u x 21/u

I/u = 1 x 21

21 = I/u

The problem is I'm completely drawing a blank. Any help would be appreciated.

Thanks,

Crazysah

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# Basic Relativity Question

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