Displacement given coefficient of friction and velocity

[mandy9008]

Homework Statement

A car is traveling at 56.0 km/h on a flat highway. 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?

Homework Equations

μ=-a/g
v²=vo² + 2 a x

The Attempt at a Solution

56.0 km/h = 15.6 m/s

0.100=-a / 9.8 m/s²
a= 0.98 m/s²

0=(15.6 m/s)² + 2 (0.98m/s²) x
x= 245.3 m

 

[PhanthomJay]

0=(15.6 m/s)² + 2 (0.98m/s²) x
x= 245.3 m

Your equation is good but check your math(s)...and minus sign

 

[mandy9008]

oh i accidently subtracted instead of divided. oops thanks!

 

[Halifaxwest]

How do you no the equation:
the coefficient of friction=-a/g ?