physics
posted by John .
John is driving at 25m/s. When he brakes, he accelerates at the rate of 5.0m/s^2.
How much time did it take him to stop?
How far does it take him to stop?

physics 
Damon
v = Vi + a t
at end v = 0 so
0 = 25  5 t
t = 5 seconds
d = vi t + .5 a t^2
d = 25(5)  2.5 (25)
d = 125  62.5
d = 62.5
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