Coefficient of Friction at constant speed

AI Thread Summary
The discussion centers on calculating the coefficient of friction for two equal masses on a rough wedge inclined at angles of 53 and 47 degrees. The user initially derives an equation based on the balance of forces, leading to a coefficient of friction calculation of u = 0.052, which they believe is incorrect. Another participant validates the user's approach, questioning why they think their result is wrong. The conversation highlights the complexities of analyzing forces on inclined planes and the importance of understanding the wedge's geometry in friction calculations. The user seeks further clarification on their calculations and the concept of a wedge.
Tensaiga
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Hello, please help me out on this:
Two equall masses lie on each side of a rough wedge, connected by a string, the wedge makes anlges 53, and 47, to the horizontal, find the coefficient of friction for the masses to move at a constant speed.

MY THINKING:
since masses are equal:
mgsin(53) = mgcos(53)(u) + mgcos(47)(U) + mgsin(47) ---> these are all the opposing forces, and force of fricton of each mass, since the slop is different for them.
the mg(s) cancels out. Leaving:
sin(53)-sin(47) = (cos53+cos47)(u)
then i got u = 0.052
which is wrong...
 
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I do not know what a wedge* is, but I imagine the situation which was more probable with the given data.

Is \mu_k = 0.098? :wink:
If it is, then I will explain my thoughts. :smile:

*My english needs improvements. :approve:
 
Tensaiga said:
MY THINKING:
since masses are equal:
mgsin(53) = mgcos(53)(u) + mgcos(47)(U) + mgsin(47) ---> these are all the opposing forces, and force of fricton of each mass, since the slop is different for them.
the mg(s) cancels out. Leaving:
sin(53)-sin(47) = (cos53+cos47)(u)
then i got u = 0.052
which is wrong...
Your thinking looks OK to me. Why do you think it's wrong?
 
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