When in orbit, a communication satellite attracts the earth with a force of 15.1 kN and the earth-satellite gravitational potential energy (relative to zero at infinite separation) is - 1.49×10^11 J. Take the radius of the Earth to be r_e = 6.38×106 m.(adsbygoogle = window.adsbygoogle || []).push({});

Find the satellite's altitude above the earth's surface.

We know that the gravitational potential energy is U = -(GMeM)/r, and it is given to be -1.49 x 10 ^11.

We also know the gravitational force to be Fg = (GMeM)/r^2

I am not sure, but can we set the two equations equal to each other and solve for r

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# Homework Help: Find the satellite's altitude above the earth's surface

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