Two identical balls A and B are moving with velocity $+0.5 ms^{-1}$ and $-0.3 ms^{-1}$ respectively. They collide head on elastically then their velocities after collision will be :

Question

$\begin{array}{1 1} (1)\; \text{$-0.3 ms^{-1}$ & $0.5 ms^{-1}$} \\ (2)\; \text{$+0.5 ms^{-1}$ & $+0.3 ms^{-1}$} \\ (3)\; \text{$-0.4 ms^{-1}$ & $0.3 ms^{-1}$} \\ (4)\; \text{$0.3 ms^{-1}$ & $-0.4 ms^{-1}$} \end{array}$