Question

10. The period of revolution of a certain planet in an orbit of radius R is T. Its period of

revolution in an orbit of radius 4R will be:

a. 2T

b. 2√2

c. 4T

d. 8T​

Answer 1

Answer:

8T

Explanation:

From Kepler's 3rd law

T² ∝ R³ ==> T ∝ R³/²

Hence for orbit of radius 4R the time period is:

T'/T = (4R/R)³/²

T' = 8T