GravitationHard
Question
A mass 6 × 1024 kg ( = mass of earth) is to be compressed in a sphere in such a way that the escape velocity from its surface is 3 × 108 m/s (equal to that of light). What should be the radius of the sphere ?
Options
A.9 mm
B.8 mm
C.7 mm
D.6 mm
Solution
As, ve = 
, R = 
, ∴
= 9 × 10-3m = 9 mm
, R = , ∴ = 9 × 10-3m = 9 mmCreate a free account to view solution
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