Minimum distance in which the car will stop?

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To determine the minimum stopping distance for a car traveling at 51.0 mi/h on a rainy day with a static friction coefficient of 0.100, the mass of the car is not necessary for the calculation. The force of friction can be expressed in terms of the normal force, which is dependent on the car's mass, but ultimately, mass cancels out in the equations. Using kinematic equations, specifically v^2 = v_0^2 + 2aΔx, allows for the calculation of stopping distance once acceleration is determined from the frictional force. The discussion also raises the possibility of using conservation of energy to simplify the problem. The key takeaway is that while mass is typically needed for force calculations, it does not affect the final result for stopping distance in this scenario.
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Homework Statement


A car is traveling at 51.0 mi/h on a horizontal highway.
If the coefficient of static friction between road and tires on a rainy day is 0.100, what is the minimum distance in which the car will stop?

Homework Equations


<br /> \Sigma \vec{F} = m \vec{a}<br />

<br /> v^2 = v_0^2 + 2 a \Delta x<br />

<br /> f_s \leq \mu_s N<br />

The Attempt at a Solution


Is it possible to do this problem without mass? Or did my teacher just forget to give us the mass?

If I had the mass of the car, I'd use it to find the normal force, and then plug that into the friction equation to find the force of friction...and then plug that into Newtons 2nd to find acceleration, and then use kinematics to find distance.

I suppose the minimum distance would be 0 if the car's mass was infinite but...I don't think that's what he's looking for.
 
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masses should drop out at the very end. Are you allowed to use conservation of energy? If you can than its just as simple as knowing the work done by the road and brakes
 
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