The following formula relates the distance s (in feet) traveled by a vehicle during an emergency stop to the time t (in seconds) it takes to arrive at a complete stop: s=16t^2
At the scene of an accident, Bill uses skid marks to determine the braking distance of one of the vehicles involved was 656 feet.
What is the corresponding braking time?
656 = 16 t^2
t^2 = 656/4
t = sqrt (164)
t = 12.8 seconds
By the way
with acceleration a in general
s = (1/2) a t^2
if 1/2 a = 16, then a = 32 ft/s^2
which is about the acceleration of gravity.
Those tires must have spikes.
of course the next step is fo find that speed
v = a t
v = 32 * 12.8 = 410 ft/s
which is 280 miles/hour !!!
good grief