Acar travels on a straight, level road. (a) starting from rest, the car is going 38 ft/s (26 mi/h) at the end of 4.0 s. what is the car's average acceleration in ft/s2? (b) in 3.0 more seconds, the car is going 76 ft/s (52 mi/h). what is the car's average acceleration for this time period?

Explanation:

A body has acceleration when there is a change in the velocity vector, either in magnitude or direction. In this case we only have a change in magnitude. The average acceleration represents the speed variation that takes place in a given time interval.

a)

b)

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at right angles to each other