Hey all,(adsbygoogle = window.adsbygoogle || []).push({});

First-time poster here, hope y'all can help me. I'm ok with 85% of my homework this evening, but this one darned problem keeps tripping me up.

Real quick, just to note, I'm still in high school, but this is Physics AP, so let me know if I'm in the wrong forum. Thanks!

(a) Calculate the magnitude of the gravitational force exerted on a 425-kg satellite that is a distance of two earth radii from the center of the earth.

(b) What is the magnitude of the gravitational force exerted on the earth by the satellite?

(c) Determine the magnitude of the satellite's acceleration.

(d) What is the magnitude of the earth's acceleration?

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Now, I know somehow I need to incorporate this formula:

W = G * (Mem/ r^2)

W is the weight. I don't have this because I have a mass but not an acceleration.

G is always the same (6.67 * 10^-11)

Me (mass of earth) = 5.98 * 10^24kg

m(mass) = 425 kg

r (radius of earth) = 6.38 *10^6

So I know I can just plug and chug in that formula and solve for W. But I don't think that really helps me.

Am I way off here? Or just missing a small detail? And now I'm also reading that as the distance increases, the gravitational force decreases. How in the world do I incorporate this?

Thanks for any help you can provide me.

EDIT- For what it's worth, I went ahead and solved for W. I got 3.45 * 10^30

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# Homework Help: Force Magnitudes, directions, gravity, etc (lost)

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