Coefficient of friction for a car sliding down an icy hill

AI Thread Summary
To find the coefficient of friction for a car sliding down an icy hill inclined at 1.6 degrees, one must analyze the forces acting on the car using a free body diagram and apply Newton's laws of motion. The coefficient of static friction can be determined as the tangent of the hill's angle when the car is on the verge of slipping. The discussion highlights the importance of knowing whether the car is accelerating or moving at a constant speed, which was clarified later in the conversation. Ultimately, using the tangent of 1.6 degrees yields the correct coefficient of friction for the scenario described. Understanding the conditions of motion is crucial for solving such physics problems accurately.
Capncanada
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Homework Statement



A car is sliding down an icy hill inclined at 1.6 degrees, find the coefficient of friction.


Homework Equations



f_k=\mu_k*n

The Attempt at a Solution



Don't know how to begin it only given the angle of the hill.
 
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Draw a free body diagram of the car. Mark all the forces on it. Then apply Newton's laws of motion.
 
Capncanada said:

Homework Statement



A car is sliding down an icy hill inclined at 1.6 degrees, find the coefficient of friction.


Homework Equations



f_k=\mu_k*n

The Attempt at a Solution



Don't know how to begin it only given the angle of the hill.

If you do all the manths with component, you will find that the co-efficient of static friction is the tangent of the angle of the hill when the body is on the point of slipping.
One problem with this question is we don't know if this is the smallest angle for which it will slip?

If it slips at 1.6 degrees, it will certainly slip at 10 degrees, but did it slip and 1.5? 1.4? 1.3 ? ...

Also I noted that your forumula had the subscript k - presumably meaning the kinetic [moving situation] If the car is sliding down the hill but NOT accelerating, then tan1.6 will give the co-efficient you seek. However, we are not told whether it is accelerating or not?
 
PeterO is right. This problem cannot be solved without knowing the acceleration of the car.
 
I'm sorry, I forgot to add that it's sliding at a constant speed. Should've copied it word for word.

EDIT: Tangent of 1.6 gives the correct coefficient, thanks. I don't understand why though, going to read over the problem and your input.
 
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