A body under the action of several forces will have zero acceleration
When the body is very light
When the body is very heavy
When the body is a point body
When the vector sum of all the forces acting on it is zero
A body under the action of several forces will have zero acceleration
$\vec a = \frac{{\vec F}}{m}$.
If $\vec F = 0$ then $\vec a = 0$.
If $\vec F = 0$ then $\vec a = 0$.