A force `F_1` acts on a particle so as to accelerate it from rest to a velocity v. The force `F_1` is then replaced by `F_2` which decelerates it to rest

Options

A. `f_1` may be equal to `f_2`
B. `f_1`must not be equal to `f_2`
C. `f_1 `and `f_2 ` must be zero
D. `f_1 ` must be equal to `f_2`

Answer

A

Explanation

According to condition of motion under two forces, `f_1 ` and `f_2` must be acting in opposite directions and may be equal, not necessarily must be equal.