The formula for the time is Time = (speed) / (acceleration) .
If it slows 4 m/s every second, it takes (24/4) = 6 seconds to slow from 24 to zero.
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If the speed at the beginning or end of the acceleration is zero, then the formula
for distance during acceleration is D = 1/2 (acceleration) (time)² .
1/2 (acceleration) x (time)² = 1/2 (4) (6)² = 1/2 (4) (36) = 72 meters.
