A satellite of mass 500kg orbits the Earth in a circular path with radius 1.0e^7 m .

Question

1) What is the period of the satellite?

I know that the equation is

T= 2(pi)r^3/2 / sqrt GmE

mE = 5.98e^24

does G = 6.67e^-11 ??

Answer 1

T=2•π•R•sqrt(R/Gm)
the gravitational constant G =6.67•10^-11 N•m²/kg²,
Earth’s mass is M = 5.97•10^24 kg,
Earth’s radius is R = 6.378•10^6 m

Answer 2

How did you get 6.378e^6 for R?

Answer 3

From reference book