Two planets have masses M and 16M and their radii are a and 2a, respectively. The separation between the centres of the planets is 10a. A body of mass m is fired from the surface of the larger planet towards the smaller planet along the line joining their centres. For the body to be able to reach at the surface of smaller planet, the minimum firings speed needed is:

Option 1 -

2√(GM/a)

Option 2 -

4√(GM/a)

Option 3 -

√(GM²/ma)

Option 4 -

(3/√2)√(5GM/a)

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Answered by

alok kumar singh | Contributor-Level 10

a month ago

Correct Option - 4

Detailed Solution:

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