Is the velocity of arrow just when it was released from the bow same as that with which it strikes the pendulum?

Yes, the velocity of the arrow when it is released from the bow is the same as the velocity with which it strikes the pendulum, assuming no external forces like air resistance act on it. The arrow's initial velocity is conserved until it impacts the pendulum, meaning that its speed remains constant in the absence of such forces. However, in real-world scenariOS, factors like air resistance can slightly reduce its velocity before impact.