What is the average acceleration of a jet ski that goes from rest to 10 m/s west in 4 s? Take the direction west to be positive, and east to be negative.

A. 2.5 m/s^2

B. - 2.5 m/s^2

C. 0.4 m/s^2

D. - 0.4 m/s^2

In the given question all the information's required to find the correct answer is already given. We can now write the given information's separately for using in the formula for finding the average acceleration.

Initial velocity = 0 m/s

Final Velocity = 10 m/s

Since jet ski is going from east to west, so the velocity is positive.

Initial Time = 0 sec

Final Time = 4 sec

Then we can find the average acceleration from the formula

Average Acceleration = (Final Velocity - Initial Velocity) / (Final Time - Initial Time)

= (10 - 0) / (4 - 0)

= 10/4

= 2.5

So the average acceleration of the jet ski is 2.5 m/s^2. So the correct option in the given question is option "A".