Gravitation Question 171
Question:A planet has twice the radius but the mean density is $ [\frac{1}{4}th] $ as compared to earth. What is the ratio of escape velocity from earth to that from the planet[MH CET 2004]
Options:
A) 3 : 1
B) 1 : 2
C) 1 : 1
D) 2 : 1
Show Answer
Answer:
Correct Answer: C
Solution:
$ [v=R\sqrt{\frac{8}{3}\pi \rho G}] $
Þ $ [\frac{v _{p}}{v _{e}}=\frac{R _{p}}{R _{e}}\sqrt{\frac{{{\rho } _{p}}}{{{\rho } _{e}}}}] $ =$ [2\sqrt{\frac{1}{4}}=1] $
