Forta care actioneaza asupra corpului introduce energie in sistem.Dupa parcurgerea celor 1,5m , toata energia respectiva se va fi transformat in energie cinetica.
Se aplica legea variatiei:
[tex]\mathtt{E_f-E_i=L_F}[/tex]
[tex]\mathtt{\frac{mv^2}{2}=Fd}[/tex]
[tex]\mathtt{mv^2=2Fd}[/tex]
[tex]\mathtt{v=\sqrt{\frac{2Fd}{m}}=\sqrt{\frac{2\cdot1N\cdot1,5m}{1kg}}=\sqrt3\frac{m}{s}\approx1,73\frac{m}{s}}[/tex]