Question

The time period of a satellite revolving around earth in a given orbit is 7 hours. If the radius of orbit is increased to three times its previous value, then approximate new time period of the satellite will be

• A. 40 hours
• B. 36 hours
• C. 30 hours
• D. 25 hours

Answer 1

Answer: (B)

36 hours

Answer 2

The correct answer is (B) : 36 hours
$T_{2}^2 = ( \frac{R_2}{R_1} )^3 T^2{_1}$
$⇒ T_2 = (3)^{3/2} × 7 ≈ 5.2 × 7$
T2 ≅ 36 hrs