How to claculate the speed of 2.0 and 16.2 j
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Réponse :
[tex]E_c = \frac{1}{2} mv^2\\<=>\\v=\sqrt{\frac{2E_c}{m} }[/tex]
[tex]v=\sqrt{\frac{2\times 16.2}{2.0} }[/tex]
[tex]v=4.0\:m.s^{-1}[/tex]