Calculating Average Acceleration: Rebounding Hockey Puck Example

[charlotte1208]

A hockey puck rebounds from a board as shown in Figure 16. The puck is in contact with the board for 2.5ms. Determine the average acceleration of the puck over the interval.

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The answer given in the textbook is 7.3 × 10³ m/s² [7.5° N of W]. That seems like way too high of a number. Especially since the puck slows down after it strikes the board. Can someone either explain to me why that is the answer, or let me know if the textbook answer is wrong? The textbook does sometimes tend to misprint answers.

 

[Doc Al]

Looks about right. Do the calculation and see for yourself. Realize that the change in velocity takes place over a very short time, only 2.5 milliseconds.