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A car driving on the turnpike accelerates uniformly in the positive x direction from 98.0 ft/s (66.8 mph ) to 121 ft/s (82.5 mph ) in 3.60 s .

How far does the car travel while it accelerates?

Verified Answer :

AL2006

The car accelerates from 98 f/s to 121 f/s . . . a relatively modest 0.2 G .

Its average speed during the acceleration is  (1/2) (98 + 121) = 109.5 f/s .

Moving at an average speed of 109.5 f/s for 3.6 seconds,
the car travels

           (109.5 f/s) x (3.6 s)  =  394.2 feet .


The Rest of the Story:
The car then immediately slows from 121 f/s to zero in the next 2 seconds,
because after reaching the speed of  82.5 mph and covering 394.2 feet,
it turns out that there is a Highway Patrol car with speed radar at about the
400-ft mark, whose red beacons are flashing even before the car gets there.

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