A nucleus disintegrated into two nuclei and their velocities are in the ratio of 2:1. What will be the ratio of their size ?

Explanation

From the law of conservation of momentum, the two nuclei will have the same magnitude of momentum. Hence, mass `prop 1/"velocity"` .Again , mass `prop R^3` , where R is the radius.
`therefore` mass `prop R^3 prop 1/"velocity" " " therefore R_1/R_2=(v_2/v_1)^(1/3) = (1/2)^(1/3)`
`therefore R_1:R_2 = 1:2^(1//3)`