A ball rolls along a horizontal road with an initial speed of

PHYSICS · Subjective · A Level · Physics · Mechanics and materials · Mechanics and materials

Problem

3\,\text{m/s}

. The surface provides a retarding acceleration of

0.5\,\text{m/s}^2

. After

2\,\text{s}

, the surface suddenly becomes perfectly smooth and offers no opposing force. What will be the speed of the ball at

t = 4\,\text{s}

? Show your working.