Question

What is the greatest safe speed, without skidding, that a 1700 kg car can have on a level curve of radius 215 meters if Mk=0.4 and Ms=.85?

Answer=42.3

I tried using the equation mv^2/r=mg+Mk.

Answer 1

forcefriction=forcecentripetal
mg*mu=mv^2/r
v=sqrt (r*mu*g)=sqrt(.4*9.8*215)=29m/s

Answer 2

I got 29 the first time I tried it too. That's not the correct answer. I posted the correct answer above.

Answer 3

I just don't know how to get it.