Coefficient of friction question.

AI Thread Summary
The discussion revolves around calculating the coefficient of friction on a wet racetrack, given a maximum safe speed of 77 km/hr and a radius of curvature of 53 m. The relevant equation used is (gravity)*(coefficient) = (v^2)/r, with the speed converted to 21.39 m/s. A participant initially calculated the coefficient as 0.8488 but realized they mistakenly used the wrong radius of 55 meters instead of the correct 53 meters. This error led to confusion, highlighting the importance of accurate data in physics calculations. The discussion emphasizes the need for careful attention to detail in problem-solving.
JohnnyB212
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Homework Statement



On a wet racetrack, the maximum safe speed, to avoid sliding on a level circular curve with a radius of curvature of 53 m, is 77 km/hr. What is the coefficient of friction between the car's tires and the track surface?

Homework Equations



(gravity)*(coefficient) = (v^2)/r

V= 21.39 m/s (after changing 77 km/hr into m/s)
Radius= 55 meters


The Attempt at a Solution



I kept getting the same answer .8488, but it keeps telling me I'm wrong? Help please!
 
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Cancel that, Stupid me plugged in the wrong radius into the equation, my mistake! Sorry!
 
JohnnyB212 said:
...on a level circular curve with a radius of curvature of 53 m

JohnnyB212 said:
Radius= 55 meters

There is a discrepancy here.
 
cepheid said:
There is a discrepancy here.


Yep, I just caught this! My mistake. :frown:
 

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