Coefficient of friction for a car sliding down an icy hill

Click For Summary

Homework Help Overview

The problem involves a car sliding down an icy hill inclined at 1.6 degrees, with the goal of finding the coefficient of friction. The context is rooted in physics, specifically in the study of forces and motion on inclined planes.

Discussion Character

  • Exploratory, Assumption checking, Conceptual clarification

Approaches and Questions Raised

  • Participants discuss drawing a free body diagram and applying Newton's laws of motion. There is uncertainty about the relationship between the angle of the hill and the coefficient of friction, particularly whether the angle given is the minimum for slipping. Questions arise regarding the car's acceleration and whether it is sliding at a constant speed.

Discussion Status

The discussion is ongoing, with some participants providing guidance on the relevance of the tangent of the angle in relation to the coefficient of friction. However, there remains a lack of consensus on the implications of the car's acceleration and the conditions under which the coefficient is applicable.

Contextual Notes

Participants note that the problem lacks information about the car's acceleration and whether it is sliding at a constant speed, which are critical for determining the coefficient of friction accurately.

Capncanada
Messages
52
Reaction score
0

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.
 
Physics news on Phys.org
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.
 

Similar threads

  • · Replies 5 ·
Replies
5
Views
7K
Replies
14
Views
3K
  • · Replies 11 ·
Replies
11
Views
3K
Replies
7
Views
2K
Replies
11
Views
1K
Replies
4
Views
4K
Replies
6
Views
3K
  • · Replies 60 ·
3
Replies
60
Views
5K
  • · Replies 19 ·
Replies
19
Views
4K
  • · Replies 16 ·
Replies
16
Views
6K