A satellite orbits Neptune 4000km above its surface. given the mass of Neptune is 1.02x10^26 kg and the radius of Neptune is 2.48x10^7m, Calculate the orbital speed of the satellite

1 answer

Neptune's gravity provides the centripetal force

the orbital altitude is not significant compared with Neptune's radius

m v^2 / r = G M m / r^2

v^2 = G M / r
... = 6.67E-11 * 1.02E26 / (2.48E7)^2

result (v) is in m/s