Two identical balls $A$ and $B$ having velocities of $0.5 \mathrm{m} {\mathrm{s}}^{-1}$ and $-0.3 \mathrm{m} {\mathrm{s}}^{-1}$, respectively, collide elastically in one dimension. The velocities of $B$ and $A$ after the collision, respectively, will be

• A

  $-0.5 \mathrm{m} {\mathrm{s}}^{-1}$ and $0.3 \mathrm{m} {\mathrm{s}}^{-1}$
• Correct answer
  B

  $0.5 \mathrm{m} {\mathrm{s}}^{-1}$ and $-0.3 \mathrm{m} {\mathrm{s}}^{-1}$
• C

  $-0.3 \mathrm{m} {\mathrm{s}}^{-1}$ and $0.5 \mathrm{m} {\mathrm{s}}^{-1}$
• D

  $0.3 \mathrm{m} {\mathrm{s}}^{-1}$ and $0.5 \mathrm{m} {\mathrm{s}}^{-1}$

Hence, the correct answer is option: 'B'.