Moving a block with kinetic and static friction to find the net force?

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SUMMARY

The discussion focuses on calculating the net force acting on a block with a mass of 3.4 kg when it transitions from static to kinetic motion. The coefficient of static friction is 0.37, while the coefficient of kinetic friction is 0.14. The maximum static friction force is determined using the formula F_static = μs * m * g, resulting in a force of approximately 12.4 N. Once the block starts moving, the net force is calculated by subtracting the kinetic friction force (F_kinetic = μk * m * g) from the applied force.

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  • Ability to perform calculations involving gravitational force (g = 9.81 m/s²)
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The coefficient of static friction between a block and a horizontal floor is 0.37, while the coefficient of kinetic friction is 0.14. The mass of the block is 3.4 kg. If a horizontal force is slowly increased until it is barely enough to make the block start moving, what is the net force on the block the instant that it starts to slide?

I tried multiple ways of solving this problem, but am only down to one attempt left for credit on my homework. I don't know if I'm over analyzing the problem or what, but its giving me trouble, please help. Thank you
 
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What force is required to move the block? Or more specifically what is the greatest amount of resistance the static friction can provide?

μs*m*g

But that's the static friction. But that is the first part of what you want.

After it moves then it is opposed by the μk*m*g of the kinetic friction, so ... Your net force then is Fstatic - Fkinetic.
 
thanks again I owe you!
 

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