Can I deduce the coefficient of static friction with Mass, Velocity and Radius?

Click For Summary

Homework Help Overview

The discussion revolves around deducing the coefficient of static friction for a car on a track, given its mass, velocity, and radius of motion. The original poster presents specific values and attempts to relate them to the forces involved in circular motion.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • The original poster attempts to use the centripetal force equation to calculate the force of static friction and questions whether this can be used to find the coefficient of static friction. Other participants engage by questioning the assumptions about maximum speed and the implications of frictional force calculations.

Discussion Status

Participants are exploring the relationship between the calculated forces and the coefficient of static friction. Some guidance has been offered regarding the assumptions about maximum speed and the implications for the coefficient, but there is no explicit consensus on the correctness of the original poster's logic.

Contextual Notes

There is uncertainty about whether the calculated speed is indeed the maximum speed without slipping, which affects the interpretation of the results. The discussion also highlights the need for clarity in the details provided in the original post.

Naoki
Messages
7
Reaction score
0
The Known:
Mass=2000kg
Velocity=50m/s
Radius=1000m

With the given information the lab worksheet I'm working on is asking me to deduce the coefficient of friction so that I can manipulate the data and answer some questions. The problem I have is that I am not entirely sure that this could be done with just the given information. BTW, this is supposed to be a car on a track.

My attempt at the solution is:

Using Fs= mv^2/r I can get 2000*50^2/1000=5000N

so the question I have is can I use this as the following Fs(max) in this equation to figure out the coefficient of static friction?

Fs(max)=μn where n is the normal force or m*g witch in this case would be 2000*9.8=19,600kgs.

If were to attempt that is would be Fx(max)/n = μ 5000/19600=.26

Is my logic sound? Please help.
 
Last edited:
Physics news on Phys.org
Hi Naoki. Would you like to have another go at posting your question. None of the details have appeared in your message.
 
could you look again, I just edited it. thanks
 
Naoki said:
If were to attempt that is would be Fx(max)/n = μ 5000/19600=.26

Is my logic sound? Please help.
That looks right, assuming it can go no faster without slipping. :smile:

http://img96.imageshack.us/img96/5725/red5e5etimes5e5e45e5e25.gif
 
Last edited by a moderator:
I don't know if that is the max speed without slipping. I know that it is the Force of friction with the known. Would that change the answer?
 
Were the car able to go even faster, still without slipping, then your calculations would come up with a greater value for μ for that surface.
 

Similar threads

Replies
61
Views
4K
  • · Replies 1 ·
Replies
1
Views
2K
  • · Replies 1 ·
Replies
1
Views
4K
  • · Replies 16 ·
Replies
16
Views
3K
  • · Replies 7 ·
Replies
7
Views
4K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 8 ·
Replies
8
Views
8K
  • · Replies 10 ·
Replies
10
Views
1K
  • · Replies 3 ·
Replies
3
Views
2K
  • · Replies 3 ·
Replies
3
Views
7K