a is deacceleration
v = Vi - a t
which is = 0 at stop
0 = Vi -10 a
a = .1 Vi
X-Xi = d = Vi t - (1/2) a t^2
290 = Vi (10) - .5 a (100)
290 = 10 Vi -50 a
290 = 10 Vi -5 Vi
290 = 5 Vi
vi = 58 meters/second = .058 km/second
* 3600 seconds/hr = 209 km/hr
In a car accidnet involving a sports car, skid marks as long as 290 m were left by the car as it decelearted to a complete stop. The police report cited the speed of the car before breaking as beeing in excess of 100mph 161 km/m. Suppose that i took 10 seconds for the car to stop. Estimate the speed of the car before the brakes were applied
2 answers
By the way How on earth was I to know this was a physics question from your title? You are just lucky Ik spreek Hollands.