Find the coefficient of Friction with weight and force needed to move and object

AI Thread Summary
To find the coefficient of friction for a block weighing 9.3 N that requires a force of 3.7 N to move at constant velocity, the formula Ff = μ * Fn is used. Initially, it was calculated as μ = 3.7 N / 9.3 N, resulting in approximately 0.37755. However, clarification on the normal force indicates that it should be calculated as 9.3 N multiplied by 9.8 m/s², leading to a revised coefficient of friction of 0.406. The discussion highlights the importance of correctly interpreting weight and force in calculations. Ultimately, the correct coefficient of friction is confirmed to be 0.0406 when considering the weight as force in Newtons.
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Homework Statement


A block weighing 9.3 N requires a force of
3.7 N to push it along at constant velocity.
What is the coefficient of friction for the
surface


Homework Equations


Ff=μ*Fn


The Attempt at a Solution


So the 3.7 N to push is the Force of friction so 3.7=μ*9.3
μ=3.7/9.3=.37755

Is this correct
 
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well, i think you are close. The Normal Force is equal to the force going down, that is, mass times acceleration, because this is in one dimension. That means that you actually should do Normal Force = 9.3 * 9.8. Then you divide 3.7 by the answer, which should give you 0.406.
 
That is what i was thinking but since it said "weigh", i thought that that was already in Newtons... in other words, it was force and it was the value for normal force. Am i missing something??
 
oh, that is a good point. Sorry, I didn't notice that; in that case, you are correct. And my bad, had it been the force, the answer is actually 0.0406, not 0.406. But all is well that ends well!
 
thanks
 
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