Gravitation Question 165
Question: The escape velocity for the earth is $ [v _{e}] $ . The escape velocity for a planet whose radius is four times and density is nine times that of the earth, is[MP PET 2003]
Options:
A) $ [36,v _{e}] $
B) $ [12,v _{e}] $
C) $ [6,v _{e}] $
D) $ [20,v _{e}] $
Show Answer
Answer:
Correct Answer: B
Solution:
$ [v\propto R\sqrt{\rho }] $ \ $ [\frac{v _{p}}{v _{e}}$=$\frac{R _{p}}{R _{e}}\times\sqrt{\frac{{\rho} _{p}}{\rho} _{e}}$=$ 4\times \sqrt{9}=12] $ Þ $ [v _{p}=12v _{e}] $
