Question 10.
Solve the following problems.
How much time a satellite in an orbit at height 35780 km above earth’s surface would take, if the mass of the earth would have been four times its original mass?
Answer:
Given G = gravitational constant = 6.67 x 10-11 N m2/kg2
M mass of earth = 4 x 6 x 1024 kg
R = 6400 km
h = height of satellite above earth’s surface = 35780 km
R+h = 6400 + 35780 = 42180 km = 42180 x 103 m
v = ?
we know
v = √
=
v = 6.16 km/s
We know v = distance/time
= circumference/time
= 2πr/T
T = 
T = 
T = 43001.68 sec
T = 11.94 hr or approximately 12 hours.
