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What is the speed of the Earth's rotation?

**At the equator, the circumference of the Earth is 40,070 kilometers, and the
day is 24 hours long so the speed is 1670 kilometers/hour ( 1037 miles/hr).
This decreases by the cosine of your latitude so that at a latitude of 45
degrees, cos(45) = .707 and the speed is .707 x 1670 = 1180 kilometers/hr.
You can use this formula to find the speed of rotation at any latitude.**

**
BTW: make sure that when you use your calculator that you set up the arguments for the trig functions in terms of degrees not radiane!**

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All answers are provided by Dr. Sten Odenwald (Raytheon STX)
for the

NASA IMAGE/POETRY
Education and Public Outreach program.