Willem 's Gravesande

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Willem 's Gravesande (1688 – 1742) was a Dutch scientist and lawyer. His chief contribution to physics involved an experiment in which brass balls were dropped with varying velocity onto a soft clay surface. His results were that a ball with twice the velocity of another would leave an indentation four times as deep, that three times the velocity yielded nine times the depth, and so on. He shared these results with Émilie du Châtelet, who subsequently corrected Newton's formula E = mv to E = mv². (Note that though we now add a factor of 1/2 to this formula to make it work with coherent systems of units, the formula as expressed is correct if you choose units to fit it.) His chief publication was titled Mathematical Elements of Natural Philosophy, Confirm'd by Experiments.