Gravitation Question 161
Question: A mass of $ [6\times 10^{24}kg] $ is to be compressed in a sphere in such a way that the escape velocity from the sphere is $ [3\times 10^{8}m,/s] $ . Radius of the sphere should be $ [(G=6.67\times {{10}^{-11}}N-m^{2}/kg^{2})] $ [UPSEAT 2002]
Options:
A) 9 km
B) 9 m
C) 9 cm
D) 9 mm
Show Answer
Answer:
Correct Answer: D
Solution:
$ [v_{e}=\sqrt{\frac{2GM}{R}}=\sqrt{\frac{2\times 6.67\times {{10}^{-11}}\times 6\times 10^{24}}{R}}] $ $ [=3\times 10^{8}] $ By solving $ [R=9,,mm] $