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Q & A: Determining the coefficient of friction

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Most recent answer: 08/02/2011
Q:
How to determine friction on a horizantal plane?
- Nasiru bala mohd (age 23)
Gwale, Kano state Nigeria.
A:
If you can tilt your plane, raise it until the object moves and measure the angle θ. The tangential force is Mg sin(θ) whereas the horizontal force is Mg cos(θ). The ratio, tan(θ) is then equal to the coefficient of static friction.  
If you cannot tilt your plane then you need to have a set up with pulleys and known weights.  Attach a string to the object, thread it over the pulley and add weights until the object moves.   The ratio of the added weights to the weight of the object gives you the answer.

LeeH

(published on 08/02/2011)

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