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

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The discussion focuses on calculating the net force acting on a block when it transitions from static to kinetic motion. The coefficient of static friction is 0.37, and the coefficient of kinetic friction is 0.14, with the block's mass being 3.4 kg. To find the force required to initiate movement, the maximum static friction force is calculated using the formula μs * m * g. Once the block starts moving, the net force is determined by subtracting the kinetic friction force from the static friction force. The conversation emphasizes understanding the transition between static and kinetic friction to solve the problem effectively.
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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!
 
The book claims the answer is that all the magnitudes are the same because "the gravitational force on the penguin is the same". I'm having trouble understanding this. I thought the buoyant force was equal to the weight of the fluid displaced. Weight depends on mass which depends on density. Therefore, due to the differing densities the buoyant force will be different in each case? Is this incorrect?

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