• question_answer Two masses connected by a mass less spring .are placed on a horizontal smooth surface. The spring is initially compressed by 3 cm. The system is released from rest. The velocity (in m/s) of the 2 kg mass, when spring attains natural length is to                                                   A) $\sqrt{\frac{3}{2}}$ B) $\sqrt{\frac{2}{3}}$ C) $\frac{3}{2}$ D) $\sqrt{3}B=\left( 1/5\text{ }x\text{ }30 \right)$

[a] ${{m}_{1}}{{v}_{1}}={{m}_{2}}{{v}_{2}}$and$\frac{1}{2}Kx_{0}^{2}=\frac{1}{2}{{m}_{1}}v_{1}^{2}+\frac{1}{2}{{m}_{2}}v_{2}^{2}.$ Solving$:{{v}_{2}}=\sqrt{\frac{3}{2}}$