SOLUTION: Tricky-looking word problem that I don't know what formula to use? All it gives is the radius. "At the equator, the radius of the earth is approximately 3960 miles. Determine in

Algebra ->  Trigonometry-basics -> SOLUTION: Tricky-looking word problem that I don't know what formula to use? All it gives is the radius. "At the equator, the radius of the earth is approximately 3960 miles. Determine in      Log On


   



Question 811287: Tricky-looking word problem that I don't know what formula to use? All it gives is the radius.
"At the equator, the radius of the earth is approximately 3960 miles. Determine in MPH, the speed at which a point on the equator is moving as a result of the earths rotation about its axis. ??
Anyone know how to answer this, or how do you know which formula to use? Thanks!

Answer by josgarithmetic(39630) About Me  (Show Source):
You can put this solution on YOUR website!
Circumference is 2%2Api%2Ar=2%2Api%2A3960 miles, so a point on the circumference moves at the circular rate of 2%2Api%2A3960%2F24 miles per hour.