A rigid ball of mass m strikes a rigid wall at 60୭ and gets reflected without loss of speed as shown in the figure below. The value of impulse imparted by the wall on the ball will be : 

mv

Impulse : |\(\vec{J}| = |\vec{P_2} - \vec{P_1}\)|

                                = 2 m v cos \(\theta\)

                                = mv