Answer
After the force is applied, the ball moves in the negative direction of the x axis.
Work Step by Step
We can find the initial momentum of the ball:
$p_i = (0.40~kg)(14~m/s) = 5.6~kg~m/s$
The impulse has a magnitude of $32.4~N\cdot s$ in the negative direction.
Since the magnitude of the impulse is greater than the initial momentum of the ball, the ball's momentum after the force is applied will be in the negative direction.
After the force is applied, the ball moves in the negative direction of the x axis.
