Calculating Frictional Force: Solving for u in a Horizontal Curve | Physics Help

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SUMMARY

The discussion focuses on calculating the frictional force required to keep a 49.2 kg car moving at 12.6 m/s around a horizontal curve with a radius of 31.3 m. The user initially misinterprets the problem by solving for the coefficient of friction (μ) instead of the frictional force itself. The correct approach involves using the formula for centripetal force, where the frictional force (F_f) is calculated as F_f = m(v^2/r). The user ultimately realizes the need to directly compute the frictional force rather than the coefficient.

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mixedtape_15
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I really am not getting this physics stuff...again I thought I had this one figured out but it doesn't seem to be right.
So the question...
A 49.2 kg car is moving at 12.6 m/s around a horizontal curve whose radius is 31.3 m. What is the magnitude of the fictional force required to keep the car from sliding?

and this is what I did..
I found my net force for x and y
Fy = may
Fy = 0
N- W = 0
N = mg

Fx = max
fs = max
u x N = m(v^2/r)

so then I substituted in my N and got
u x mg = m(v^2/r)

and I solved for u (frictional force...I'm just using u for the term)

u x (49.2kg)(9.81m/s^2) = (49.2kg)(12.6^2/31.3m)

and it works out to be 0.517 and the computer is telling me I'm wrong once again. so I must be wrong.
 
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The question does not ask you to find μ. It asks you for the frictional force.
 
Thank you! I have some serious problems with reading these things wrong.
 

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