# If a nucleus disintegrates i two two nuclear parts which have their velocities in ratio 2 : 1 . The ratio of their nuclear sizes will be .

$(a)\;2^{\large\frac{1}{3}} : 1\qquad(b)\;2 : 1\qquad(c)\;4 : 1\qquad(d)\;1 : 2^{\large\frac{1}{3}}$

Answer : (d) $\; 1 : 2^{\large\frac{1}{3}}$
Explanation :
$\large\frac{R_{1}}{R_{2}}=(\large\frac{m_{2}}{2 m_{2}})^{\large\frac{1}{3}}$
$\large\frac{R_{1}}{R_{2}}= 1 : 2^{\large\frac{1}{3}}\;.$