Gravitation Question 169
Question:If the radius of a planet is four times that of earth and the value of g is same for both, the escape velocity on the planet will be[RPET 2002]
Options:
A) $ [11.2,,km/s] $
B) $ [5.6,,km/s] $
C) $ [22.4,,km/s] $
D) None
Show Answer
Answer:
Correct Answer: C
Solution:
$ [v=\sqrt{2gR}] $
Þ $ [\frac{v_{p}}{v_{e}}=\sqrt{\frac{g_{p}}{g_{e}}\times \frac{R_{p}}{R_{e}}}=\sqrt{1\times 4}=2] $
Þ $ [v_{p}=2\times v_{e}=2\times 11.2=22.4\ km/s] $
