I thought I set up the equations correctly, but the speed I got seemed too fast.(adsbygoogle = window.adsbygoogle || []).push({});

An early objection to the idea that the Earth is spinning on its axis was that Earth would turn so fast at the equator that people would be thrown into space. Show the error in this logic by calculating the speed of a 91.3kg person at the equator.

I set the equations for centripetal force and gravitational force equal to each other:

(m2v^2)/r = (Gm1m2)/(r^2)

I set m1 = earth's mass and m2 = person's mass

r was given: 6.37e6m

mass of earth: 5.98e24kg

G = 6.67259e-11

I solved for velocity and got 7914.584m/s and that seems too fast. I'm worried because they also provided the moon's radius in the givens, I hope I wasn't supposed to use that because I can't find any use for that.

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# Homework Help: Speed at the equator

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