Question

Suppose that a NASCAR race car is moving to the right with a constant velocity of +82 m/s. What is the average acceleration of the car? (b) Twelve seconds later, the car is halfway around the track and traveling in the opposite direction with the same speed. What is the average acceleration of the car?

I understand (a) but I don't understand how to solve for (b) can someone please help me?

Answer 1

As : Avg. acceleration = \(\large \cfrac{v_{final} - v_{initial} }{t_2 - t_1 }\)

[Avg. Acceleration is defined as the rate of change of velocity wrt. change in time ]

As the car is moving in opposite direction, so we will put a negative sign there with velocity. Final velocity = Initial velocity = \(- 82 m/s\)

So : \(\textbf{Average Acceleration} = \cfrac{-82 - 82 }{12} m/s^2\)

Solving it further you will get your answer as -13.66... m/s^2 or -13.67 m/s^2

Hope it helps