A hockey puck travelling at 26 m/s [E 22* S] rebounds off the board at 21 m/s [E 22* N]. The puck is in contact with the board for 0.0025 seconds. Determine the average acceleration of the puck over the interval.

average acceleration= change in velocity/time

a= (Vf - Vi)/time

Put the velocities in as vectors, and solve. Put the velcities in as N,S, E, W components.

It doesnt work I keep getting around 1880 m/s^2 when the answer should be 730.

Show me your work. Let me critique it. I think the problem is your directions.