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A black hole is an object whose gravitat...

A black hole is an object whose gravitational field is so strong that even light cannot escape from it. To what approximate radius would earth ( mass `=5.98xx10^(24)kg`) have to be compressed to be a black hole ?

A

`10^(-9)m`

B

`10^(-6)m`

C

`10^(-2)m`

D

100m

Text Solution

Verified by Experts

The correct Answer is:
C
`v_e=sqrt((2GM)/R)=C or, R=(2GM)/(C^2)`, where ,C=velocity or light
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Knowledge Check

  • At what height from the surface of earth the gravitation potential and the value of g are -5.4xx10^7J*kg^(-1) and 6 m*s^(-2) respectively ? Take the radius of earth as 6400 km.

    A
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    B
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    C
    2000 km
    D
    2600 km

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