A body of mass `20 gm` is moving with a certain velocity. It collides with another body of mass `80 gm` at rest. The collision is perfectly inelastic. The ratio of the kinetic energies before and after collision of the system isA. `2 : 1`B. `4 : 1`C. `5 : 1`D. `3 : 2`

A body of mass `20 gm` is moving with a certain velocity. It collides

1.	A body of mass `20 gm` is moving with a certain velocity. It collides with another body of mass `80 gm` at rest. The collision is perfectly inelastic. The ratio of the kinetic energies before and after collision of the system isA. `2 : 1`B. `4 : 1`C. `5 : 1`D. `3 : 2`
Answer» Correct Answer - C `m_(1) u_(2) = (m_(1) + m_(2)) v` `KE_(i) = (1)/(2) m_(1)u_(1)^(2) , KE_(f) = (1)/(2) (m_(1) +m_(2)) v^(2)`.

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A body of mass `20 gm` is moving with a certain velocity. It collides with another body of mass `80 gm` at rest. The collision is perfectly inelastic. The ratio of the kinetic energies before and after collision of the system isA. `2 : 1`B. `4 : 1`C. `5 : 1`D. `3 : 2`

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