Question

A race car’s velocity increases from 2.0 m/s to 60 m/s over a 4.0-s time interval .What is its average acceleration

Answer 1

The size of the acceleration is

          (change in speed) / (time for the change) .

Change in speed = (60 m/s  -  2 m/s)  =  58 m/s

Time for the change = 4.0 s

Size of the acceleration =  (58 m/s) / (4.0 s)  =  14.5 m/s² .

We don't know the direction of the velocities, so we can't say anything
about the direction of the acceleration.