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Frictional Forces and Coefficients of Friction [Need help!]

  • Thread starter tutojean
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  • #1
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Homework Statement


A sled is pulled at a constant speed over a horizontal surface where the kinetic coefficient of friction is .20. What is the minimum force necessary to keep the sled moving if its mass is 2 slugs?


Homework Equations



f(s)=U(s)N or f(s)=Ns(mg)

F(s)= Frictional Force
m=weight
g=gravity
(Not sure about this equation or problem)

The Attempt at a Solution



F(s) = Ns(mg)
F(s) = (.20)(2 slugs)(32 ft/s^(2))
F(s) = 12.8 N ???

Am I doing this right or wrong? Can somebody please show me how to do this?
 

Answers and Replies

  • #2
Redbelly98
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You did it right, except that the force units are not Newtons.

What force units go with feet, slugs, and seconds?
 

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