A small mass m is released in a tunnel dug across a chord of a planet. The centre of a chord is at a distance of 0.6 R from the centre of planet (where ' R ' is radius of the planet).

Question

TestHub · Accepted Answer

Force ' F ' pressing the walls of tunnel in the figure is F = m R 3 GMr ​ cos θ = R 3 GMmr ​ r 3 5 R ​ ​ N = 5 R 2 3 GMm ​ W F ​ + W g ​ = 0 ⇒ W F ​ = − W g ​ 5 R 2 μ 3 GMm ​ ( 0.8 R ) = 2 R 3 Gmm ​ ( 3 R 2 − ( 5 2 R ​ ) 2 ) − R GMm ​ μ = 3 2 ​ = 0.67

Physics - Gravitation Question with Solution | TestHub

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