Help please! A car is traveling at 53.0 km/h on a flat highway.?

A car is traveling at 53.0 km/h on a flat highway.

a) If the coefficient of friction between road and tires on a rainy day is 0.100, what is the minimum distance in which the car will stop?


(b) What is the stopping distance when the surface is dry and the coefficient of friction is 0.600?



we can use

vf^2=v0^2 + 2ad to find stopping distance where

vf = final velocity =0

v0 = initial velocity = 14.72m/s

a = acceleration

d = distance traveled = stopping distance

we can find the acceleration knowing that F = ma, and in the case of friction, f = u mg, so that

m a = u m g or a = u g

in this case, a =- 0.1 x 9.8m/s/s = -0.98m/s/s the acceleration will be negative since it opposes motion


0=(14.72m/s)^2 +2(-0.98m/s/s) d => d = 110.6m

if the coefficient of friction were 6 times greater, the accel would be 6 times greater and the stopping distance would be 1/6 as much, so it would be 18.4m


thats cheating