physics
posted by cb on .
i keep trying to put this in my calculator but i keep getting the wrong answer...can someone please try it on their calculator and help me?
thnks
(a) Find the distance r to geosynchronous orbit.
Apply Kepler's third law. T^2=((4pi^2)/(GM_E))r^3
Substitute the period in seconds, T = 86,400 s, the gravity constant G = 6.67 multiplied by 1011 kg1 m3/s2, and the mass of the Earth, ME = 5.98 multiplied by 1024 kg. Solve for r.
T^2=((4pi^2)/(GM_E))r^3

What equation are you using? You should be using Kepler's third law, and setting the satellite period to 23 hours 56 minutes (1 sidereal day)
Or check the derivation here:
http://en.wikipedia.org/wiki/Geostationary