I’m having trouble with ch3 #73 from Tipler/Mosca Physics for scientists and engineers 5th edition. I’ve tried a few things and I keep getting stuck. Am I taking the right steps?(adsbygoogle = window.adsbygoogle || []).push({});

An object resting on the equator has an acceleration toward the center of the earth due to the earth’s rotational motion about its axis, and an acceleration toward the sun due to the earth’s orbital motion. Calculate the magnitudes of both of these accelerations and express them a fraction of the magnitude of free-fall acceleration g. Use values from the physical-data table in the textbook.

So we have centripetal acceleration = v^2/r (Ac = v^2/r)

g = 9.81 m/s^2

earth’s radius @ equator = 6370 km

Ac = g^2/6370 = (9.81 m/s^2)^2/6370 km = .015 m^2/Kms^4? (what units/reductions do I need to make? Is this correct?

Period formula

v = 2PIr/T

I have 2 PI and r, but what do I use for T?

Thanks for your help!

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# Homework Help: Circular Motion and Centripetal Acceleration

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