# Homework Help: Banking curve problem cont'd ?

1. Jul 28, 2007

### matibtst

banking curve problem cont'd ????

1. The problem statement, all variables and given/known data[/b]

a curve of radius 30m is banked so that a 950kg car traveling 40 km/h can round it even if the road is so icy that the coefficient of static friction is approximately zero. Find the range of speeds at which a car can travel around this curve without skidding if the coefficient of static friction between the road and the tires is 0.3

2. Relevant equations
I've already solved for the angle and my problem is only how to equate^^

3. The attempt at a solution
Given

km/h = ??????
angle of slope = 22.78 degrees
coefficient of friction = .3
mass = 950 kg
weight = 9310 N

coefficient of friction X Normal Force = Force of Friction

$$n sintheta + f costheta = mv^2 divided by radius$$

sorry can't figure out latex

2. Jul 28, 2007

### Astronuc

Staff Emeritus
In LaTeX, the theta (or greek symbols) is preceeded by a \ , e.g. \theta.

Here is the PF tutorial on LaTeX - https://www.physicsforums.com/showthread.php?t=8997

One should solve for an angle such that the inward component of the weight of the car keeps it on the road, i.e. when ice is present and the coefficient of friction $\mu$ = 0.

Then with that angle, solve for the higher speed when the coefficient of friction $\mu$ = 0.3.

Last edited: Jul 28, 2007