## For Constant Mass

on a particle is, thus, equal to rate change of momentum of the particle without time. Generally mass of the object under consideration is constant and thus cone  be taken out of the derivative: {\displaystyle {\begin{aligned}{\vec {F}}&=m{\frac {d{\vec {v}}}{dt}}\\{\vec {F}}&=m{\vec {a}}\end{aligned}}} {\displaystyle {\begin{aligned}{\vec {F}}&=m{\frac {d{\vec {v}}}{dt}}\\{\vec {F}}&=m{\vec {a}}\end{aligned}}} For constant mass, {\displaystyle {\vec {F}}=m{\vec {a}}} ….  Read More