Question

Determine the stopping distances for a car with an initial speed of 93 km/h & human reaction time of 0.80 s, for an acceleration a=−4.0m/s2.?

Answer 1

Vi = 93000 m/3600 s
d = d coast + d braking

d coast = Vi (.8)

v = Vi + a t
0 = Vi - 4 t
solve for t
then
d braking = Vi t -(1/2)(4) t^2