A 1 kg stationary bomb is exploded in three parts having mass 1 : 1 : 3 respectively. Parts having same mass move in perpendicular direction with velocity 30 $ms^{–1}$, then the velocity of bigger part will be

Question

( A ) $15 \sqrt{2} ms^{–1}$
( B ) $\frac{15}{\sqrt 2} ms^{-1}$
( C ) $\frac{10}{\sqrt 2} ms^{-1}$
( D ) $10 \sqrt{2} ms^{-1}$