Question

Two satellites are in circular orbits around Earth. Satellite A has speed vA. Satellite B has an orbital radius nine times that of satellite A. What is the speed of Satellite B?
A. vA.9
B. vA/3
C. 3vA
D. 9vA

Answer 1

Answer:

option B

Explanation:

given,

Satellite B has an orbital radius nine times that of satellite A.

R' = 9 R

now, orbital velocity of the satellite A

$v_a =\sqrt{\dfrac{GM}{R}}$........(1)

now, orbital velocity of satellite B

$v_b=\sqrt{\dfrac{GM}{R'}}$

$v_b=\sqrt{\dfrac{GM}{9R}}$

$v_b=\dfrac{1}{3}\sqrt{\dfrac{GM}{R}}$

from equation 1

$v_b=\dfrac{v_a}{3}$

hence, the correct answer is option B