Does Weighing a Floating Block Change the Combined Weight?

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Weighing a beaker of water with a floating block will not yield a weight less than the sum of the individual components. According to Archimedes' principle, the floating block displaces an amount of water equal to its weight, resulting in a net force that does not affect the total weight measured. The combined weight of the beaker, water, and block remains constant regardless of the block's buoyancy. The discussion highlights confusion about how buoyancy affects weight measurement, emphasizing that the total weight remains unchanged. Understanding these principles is crucial for applications like engineering projects, such as the proposed strengthening of a canal aqueduct.
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5. A block of wood floats in a beaker of water. According to Archimedes’ principle, the block experiences an upward buoyant force. If the beaker with the water and floating block were weighed, would the measured weight be less than the sum of the weights of the individual components? Explain.



Homework Equations


fb = change in pressure * A



The Attempt at a Solution


I am utterly lost
 
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If the beaker with the water and floating block were weighed,
If block has mass m1 and beaker and water together have mass m2, what are the weights?

Now put block in the water. What happens to the masses? The what is the weight of the masses?
 
Don't laugh but my city council announced a proposal to strengthen a canal aquaduct so it could carry heavier barges!
 

Thread 'Magnitude of buoyant force in fluids of different densities'

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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