Physics

Problem

Block A of mass

2\,\text{kg}

is moving at

6\,\text{m s}^{-1}

along a smooth, straight track and overtakes block B of mass

4\,\text{kg}

that is moving in the same direction at

2\,\text{m s}^{-1}

. The blocks collide head-on and the collision is perfectly elastic. What is the speed of block A just after the collision? a)

1.33\,\text{m s}^{-1}

0.67\,\text{m s}^{-1}

3.33\,\text{m s}^{-1}

6.0\,\text{m s}^{-1}