Q7 of 81 Page 225

Two small bodies of masses 10 kg and 20 kg are kept a distance of 1.0 m apart and released. Assuming that only mutual gravitational forces are acting, find the speed of particles when the separation decreases to 0.5 m.

The mass of bodies is and .

Initial separation,


Final separation,


Initial velocity, ,


Let the final velocity be , .


From momentum conservation



Here, we will apply the conservation of energy,






Therefore,


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