Physics

Problem

A roller-coaster car of mass

1200\,\text{kg}

crests a hill

25\,\text{m}

high with a speed of

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

. It then descends without friction to a valley that is

5.0\,\text{m}

above the ground. Calculate its speed in the valley. a)

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

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

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

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