Comparing Horizontal Forces on Stacked Blocks with Friction

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The discussion centers on the forces acting on two stacked blocks, where the top block has a mass of 3kg and the bottom block has a mass of 2kg, with a static friction coefficient of 0.3 preventing sliding. When a horizontal force is applied to the bottom block, both blocks accelerate together, but the top block experiences a greater net force due to its larger mass. The total force acting on the bottom block, Fb, is less than that on the top block, Ft, leading to the conclusion that Ft > Fb. The reasoning hinges on the relationship between mass, acceleration, and frictional force, emphasizing the importance of horizontal forces in this scenario. Understanding these dynamics is crucial for solving similar physics problems involving friction and acceleration.
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Homework Statement


A block of mass 3kg sits on top of a block of mass 2kg. The static coefficient of friction between the blocks is μs=0.3, and this friction keeps the top block from sliding on the bottom block. There is no friction between the bottom block and the floor. A horizontal external force Fext is applied to the bottom block, causing the blocks to accelerate to the right.

How does the magnitude of the total force acting on the bottom block, Fb, compare to the magnitude of the total foce acting on the top block, Ft?

a. Ft>Fb
b.Ft=Fb
c.Ft<Fb


Homework Equations



None given but μs*N=Ffric and F=ma.

The Attempt at a Solution


I know that all of the forces in the y direction cancel but I am not sure how to tell which force is greater? I know that the answer is A but I am having trouble explaining it or showing work.
 
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In the y direction there is no acceleration of either block, thus, there is no net total force on either block in that direction. You should focus instead on the horizontal forces acting on each block. Since they both accelerate together at the same rate, which block must have the greater net total force acting on it in the horizontal direction, and why?
 
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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