How to find Coeff of kinetic friction without mass?

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To find the coefficient of kinetic friction without knowing the mass, a procedure involves using two identical blocks connected by a string over a pulley. By measuring the acceleration of the system as one block moves off the table, the forces can be analyzed. The key is to derive an expression that relates the frictional force to the gravitational force, which may allow mass to cancel out in the calculations. Relevant equations include Newton's second law and the definition of friction. The experiment can effectively yield the coefficient of kinetic friction using only the provided equipment.
pierce_E
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Homework Statement


For my Physics lab this is what my teacher handed me... I have no idea how to attack the situation, can someone help solve?
Devise a procedure for an experiment which will measure the coefficient of kinetic friction between a block of unknown mass m and the table, where the only equipment which can be used is the following:
1) A string of negligible mass
2) two blocks of unknown identical masses which are able to be attached to string
3) a pulley
4) measuring tape(s)
Derive an expression for the coefficient of friction between the table and the block in terms of g and quantities measured with the equipment above.

Homework Equations

The Attempt at a Solution

 
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Hello Pierce, :welcome:

First post on PF and you bump into a culture issue: the guidelines require an attempt on your part.
List the equations that you think are relevant,
Describe some experiments that would help you determine relevant variables, etc.

And don't worry: mass might well divide away and thus drop out of the calculations.
 
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