Is my mass calculation method correct?

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The mass calculation method presented is correct, as it accurately applies the conversion factor for volume expansion. By determining that the larger object is 500 times longer, the volume increases by a factor of 500 cubed, resulting in 125 million. Multiplying this volume factor by the original mass of 10 kg yields a total mass of 1.25 billion kg for the larger object. The logic and calculations align with the principles of density and volume. Therefore, the conclusion about the mass of the expanded object is valid.
5P@N
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Homework Statement


I have an object of a known mass, and known dimension along one axis (length).
Mass: 10 kg
Length: 2 meters

I wish to calculate what the mass of an object that is similarly constituted and shaped will be if it has a greatly expanded length of: 1,000 meters.

I am seeking to know what the mass of this larger object will be.

Homework Equations


Volume = Length * Width * Height

Conversion factor = larger object / smaller object

{ (conversion factor)^3 } * mass of smaller object = mass of larger object
(The conversion factor is cubed so as to account for all 3 volumetric dimensions of expansion)

The Attempt at a Solution


1,000 m / 2 m = 500
500 = conversion factor
(500)^3 = 125,000,000

This 125 million is then multiplied by the original mass of 10 kg, to get an answer of: 1 billion, 250 million kg.

Does anybody see a problem with my result and/or logic? Reply if you do.
 
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5P@N said:

Homework Statement


I have an object of a known mass, and known dimension along one axis (length).
Mass: 10 kg
Length: 2 meters

I wish to calculate what the mass of an object that is similarly constituted and shaped will be if it has a greatly expanded length of: 1,000 meters.

I am seeking to know what the mass of this larger object will be.

Homework Equations


Volume = Length * Width * Height

Conversion factor = larger object / smaller object

{ (conversion factor)^3 } * mass of smaller object = mass of larger object
(The conversion factor is cubed so as to account for all 3 volumetric dimensions of expansion)

The Attempt at a Solution


1,000 m / 2 m = 500
500 = conversion factor
(500)^3 = 125,000,000

This 125 million is then multiplied by the original mass of 10 kg, to get an answer of: 1 billion, 250 million kg.

Does anybody see a problem with my result and/or logic? Reply if you do.
Looks fine to me.
 
You want to make it 500 times longer, wider, and thicker, so it will have a volume that's ##(500)^3## times bigger. Assuming you keep the density of the object the same, the mass will increase by the same factor:$$10 \ \mathrm{kg} \times (500)^3=1.25 \times 10^9 \ \mathrm {kg}$$
 
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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