Find Coeff. of Static Friction of Car on Track

AI Thread Summary
To find the coefficient of static friction for a car on a circular track, the problem involves calculating the velocity at which the car skids off after accelerating uniformly. The car travels 0.2 of the way around a 5m radius track with a tangential acceleration of 1.7m/s². The equations of motion and forces are applied, leading to the relationship between centripetal force and frictional force. The initial calculations yield a coefficient of static friction around 0.436, but errors in computation or assumptions may lead to incorrect results. Further clarification or alternative methods may be needed to resolve discrepancies in the calculations.
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Homework Statement


A car traveling on a flat circular track of radius 5m accelerates uniformly from rest with a tangential acceleration of 1.7m/s^2. The car makes it 0.2 of the way around the track before skidding off. Acceleration of gravity=9.8m/s^s.
What is the coefficient of static friction between the car and the track?


Homework Equations


Fc=V^2m/r
F=ma

The Attempt at a Solution



So I tried this:
Fc=Ff
V^2m/r=\mumg
v^2/gr=\mu

To determine the velocity at which the car slips, I said V^2=2ax, where x is 2\pir/5.

So I get 4\pia/5g=\mu

It's not correct. Why is that?
 
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Nice solution. I get 0.436, but I'm prone to calculation errors.
 
The online homework system marks it wrong. I can't explain it. Is there another way to do this?
 
Kindly see the attached pdf. My attempt to solve it, is in it. I'm wondering if my solution is right. My idea is this: At any point of time, the ball may be assumed to be at an incline which is at an angle of θ(kindly see both the pics in the pdf file). The value of θ will continuously change and so will the value of friction. I'm not able to figure out, why my solution is wrong, if it is wrong .
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