"It is important to note that we cannot derive a general expression for Newton's second law for variable mass systems by treating the mass in F = dP/dt = d(Mv) as a variable.
Eshte e rendesishme te theksojme se ne nuk mund te derivojme nje ligj te pergjithshem per ligjin e edyte te Njutonit per sisteme me mase variable duke e trajtuar masen ne ekuacionin F = dP/dt = d(Mv) si nje variabele.