A trolley moves to the right (positive -direction) toward a trolley at rest on a…

PHYSICS · Single correct · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

2\,\text{kg}

trolley moves to the right (positive

x

-direction) toward a

3\,\text{kg}

trolley at rest on a frictionless horizontal track. After a perfectly elastic head-on collision, the

2\,\text{kg}

trolley is observed to move to the left at

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

, while the

3\,\text{kg}

trolley moves to the right at

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

. Determine the initial speed of the

2\,\text{kg}

trolley. (a)

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

(b)

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

(c)

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

(d)

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