Question

When forces F${}_1$, F${}_2$ and F${}_3$ are acting on a particle of mass m such that F${}_2$ and F${}_3$ are mutually perpendicular, then the particle remains stationary. If the force F${}_1$ is now removed then the acceleration of the particle is

• A.
• B.
• C.
• D.

Answer 1

The correct option is A

$\overrightarrow{F_1}+\overrightarrow{F_2}+\overrightarrow{F_3}=0\therefore \overrightarrow{F_1}=-(\overrightarrow{F_2}+\overrightarrow{F_3})$
If $F_1$ is removed, the resultiant of $\overrightarrow{F_2}$ and $\overrightarrow{F_3}$ is $F_1$ in magnitude so acceleration $=\frac{F_1}{m}$