Physics

Problem

250\,\text{g}

tennis ball is served horizontally at

72\,\text{km}\,\text{h}^{-1}

. Determine its translational kinetic energy in joules, expressed to two significant figures. a)

4.0\times10^{1}\,\text{J}

1.0\times10^{2}\,\text{J}

5.0\times10^{1}\,\text{J}

2.5\times10^{1}\,\text{J}