c
(c)Force = Rate of change of momentum Initial momentum \({\vec P_1} = mv\sin \theta \;\hat i + mv\cos \theta \,\hat j\)

Final momentum \({\vec P_2} = - mv\sin \theta \;\hat i + mv\cos \theta \,\hat j\)  

\(\vec F = \frac{{\Delta \vec P}}{{\Delta t}} = \frac{{ - 2mv\sin \theta }}{{2 \times {{10}^{ - 3}}}}\)

Substituting \(m = 0.1 kg, v = 5 m/s\),

\(\theta = 60°\) Force on the ball \(\vec F = - 250\sqrt 3 N\)

Negative sign indicates direction of the force