Solving Force and Rest with a Skater on Ice

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The discussion focuses on a physics problem involving a 68.5 kg skater who comes to rest due to friction on ice. The key equation used is F = ma, where the user initially struggles to find acceleration with time as the variable. They realize that acceleration can be calculated by dividing the initial velocity by the time taken to stop. The user expresses a moment of confusion but quickly corrects themselves, indicating a common learning experience in physics. The thread highlights the importance of understanding basic kinematic equations in solving motion problems.
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Homework Statement


here's the problem
A 68.5 kg skater moving initially at 2.40 m/s on rough horizontal ice comes to rest uniformly in 3.52 s due to friction from the ice.


Homework Equations


F= ma

The Attempt at a Solution


I'm sure this equation is reliant on finding the acceleration, but I really don't know how to do that when time (instead of distance) is our given variable
anyone know what I'm missing?
 
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okay sorry scratch that I just had a brain fart or something -.-
obviously a= m/s2 so there for all I had to do was divide the velocity by the time
I swear to god I'm getting stupider sometimes
 
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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