The Masses And Radii Of The Earth And Moon Are M1, R1 and M2, R2respectively. Their Centres Are At Distance d apart. What Is The Minimum Speed With Which A Particle Of Mass m should Be Projected From A Point Midway Between The Two Centres So As To Escape To Infinity?

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The masses and radii of the earth and moon are M1R1 and M2R2respectively. Their centres are at distance d apart. What is the minimum speed with which a particle of mass m should be projected from a point midway between the two centres so as to escape to infinity?


Correct option is


Potential energy of m when it is midway between M1 and M2,



And as potential energy at infinity is zero, so work required to shift m from the given position to infinity,


As this work is provided by initial kinetic energy,  





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k = 1.38 × 10–23 JK–1, mass of oxygen molecule = 5.3 × 10–26 kg.)


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