Centripetal Force: Calculating Radius of Curve for 1.00 x 10^3 kg Car

[dance_sg]

Homework Statement

A 1.00 x10^3 kg car is moving through a flat curve on a road at a velocity of 30.0 m/s. If the coefficient of friction between the road and the tires is 0.600, the radius of the curve is

Homework Equations

r=v^2/(coefficitent of friction)(g), r=mv^2/F

The Attempt at a Solution

I tried two ways so solve this question, but I am not sure which was is correct.
the first thing i did was, find F by multiplying 9.81m/s2 and the mass (1000). then plugging that into the r=v^2/f. Then i used the first formula i provided above and just plugged all the variables in (excluding mass). Does the mass need to somehow be in there?

 

[diazona]

In $r = mv^2/F$, the force should be the centripetal force that holds the car in the curve, not the weight of the car.

 

[dance_sg]

so 30^2 divided by 0.600 times 9.81m/s2 giving me 153m, would be the correct answer?

 

[diazona]

Yep, that's it. But you should make sure you get the same answer both ways.

 

[dance_sg]

Alrite. thank you =)