Gravitation Question 155
Question: The least velocity required to throw a body away from the surface of a planet so that it may not return is (radius of the planet is $ [6.4\times 10^{6}m,,,g=9.8,m/sec^{2})] $ [AMU (Engg.) 1999]
Options:
A) $ [9.8\times {{10}^{-3}}m/sec] $
B) $ [12.8\times 10^{3}m/sec] $
C) $ [9.8\times 10^{3}m/sec] $
D) $ [11.2\times 10^{3}m/sec] $
Show Answer
Answer:
Correct Answer: D
Solution:
Escape velocity from surface of earth
$ [v _{e}=\sqrt{2gR}] $ = $ [\sqrt{2\times 9.8\times 6.4\times 10^{6}}=11.2\times 10^{3}\ m/s] $
