Question

The time period of a satellite of earth is 90 minutes. If the separation between the earth and the satellite is quadrupled, the new time period will be _____________

(a) 90 minutes

(b) 180 minutes

(c) 560 minutes

(d) 720 minutes

I got this question by my school principal while I was bunking the class.

My doubt stems from Gravitation topic in chapter Gravitation of Physics – Class 11

Answer 1

Right choice is (d) 720 minutes

Explanation: The time period is directly proportional to the radius of orbit raised to the power of 1.5.

If the radius is quadrupled, the time period increases by 8 times.

Hence, the new time period = 90 x 8 = 720 minutes.