here's the question (from mastering physics):(adsbygoogle = window.adsbygoogle || []).push({});

"The weight of a person at the equator, as determined by a spring balance, is 750 N. By how much does this differ from the true force of gravitational attraction at the same point? Assume that the earth is spherically symmetric."

Now, i would assume what needs to be done is first finding the mass of the person (750 N / 9.8 m/s^2). then plugging that into the equation:

F = (G*m*M_e)/(R_e^2), using M_e = 5.92*10^24 kg and R_e = 6.38*10^6 m

Then, subtracting that from 750 N. I did this, and came out with 3 different answers depending on my value for acceleration (9.8 or 9.81) and how many figures i used from that figured mass. They were 1.62, 2.09, and 1.32. Mastering Physics told me those were all wrong.

...what?

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# Homework Help: Gravitation person weight problem

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