A block moving at collides head-on with a block moving at in the opposite direction

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

Problem

2\,\text{kg}

block moving at

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

collides head-on with a

3\,\text{kg}

block moving at

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

in the opposite direction. After the impact the two blocks stick together. The loss of kinetic energy in the collision is (a)

31\,\text{J}

(b)

54\,\text{J}

(c)

29\,\text{J}

(d)

19\,\text{J}