Finding Coefficient of Kinetic Friction

AI Thread Summary
To find the coefficient of kinetic friction, first calculate the normal force using the mass of the block and gravity, resulting in 2.5604 N. The net force acting on the block can be determined using the equation Fnet = m*a, which gives a force of -1.909 N. The friction force can then be expressed as Ff = μk * FN, where μk is the coefficient of kinetic friction. By setting the friction force equal to the net force, the equation can be rearranged to solve for μk. The discussion emphasizes the need to relate the measured deceleration to the friction force to find the coefficient accurately.
Ryan Hwang
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Homework Statement


See, I was collecting data for a lab, and now when I look it at, I'm being asked to find the kinetic friction force and the coefficient of friction. What I was given was:
the mass of the block: .261 kg
gravity: 9.81 m/s2
the acceleration: -7.3125 m/s2
And that's it. If it helps we were pushing blocks and used a motion detector to determine the rate of deceleration.

Homework Equations


μk*FN=Ff
FN=m*g
Fnet=m*a

The Attempt at a Solution


Let's say I start with the normal force, which I get 9.81m/s2*.261kg=2.5604N
From there I can't see any more steps I can take. The only forces acting on the object are the friction force, the applied force, which was not measured, gravity, and the normal force. Given the equation and with the task of finding two unknowns, I'm clueless on how to continue.
 
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So if I understand correctly, you were pushing blocks and then letting go and measuring the deceleration? So the deceleration is measured after you stop pushing on the block?
 
So, comparison of the force deemed to be retarding the block, and the force of the block on the surface will reveal the friction co-efficient?
 
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