Trying to find volume given Newtons/ archimedes principle

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To find the volume of a paperweight using Archimedes' principle, the difference in weight between air and water is calculated, revealing a weight of displaced water at 2.6 N. This weight is then converted to mass by dividing by the acceleration due to gravity (9.81 m/s²), resulting in a mass of 0.265 kg. The volume is determined by dividing this mass by the density of water (1000 kg/m³), yielding a volume of 2.65E-4 m³. The calculations illustrate the relationship between weight, mass, and volume in fluid mechanics. Understanding these principles is essential for solving similar physics problems.
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Homework Statement



A paperweight, when weighed in air, has a weight of W = 6.6 N. When completely immersed in water, however, it has a weight of Win water = 4.0 N. Find the volume of the paperweight.


Homework Equations



Fb = Wfluid


The Attempt at a Solution



I can find density using density of object/density of water=weight of object/initial weight-immersed weight

but can not seem to find out how to find volume... I am stuck
 
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The difference between the two weights is the weight of the displaced water, isn't it? What volume of water has a weight of 2.6N?
 
I am not sure.. I know that Newtons are kg/s^2 I just don't know how it relates in any way to volume
 
Newton's are kg*m/s^2. They are a unit of force. They have the same units as m*a (in F=ma). Volume relates to mass through density. Mass relates to force through weight equals mg (m is mass and g is the acceleration of gravity). You might want to review some of these topics.
 
The nitty gritty of it is as follows.
the Difference of the weight in the air, and the weight in the water equals weight of the object
Therefore, we use the following steps to find the volume of the object.

Step 1)
6.6 N -4.0 N = 2.6 N <--weight of water displaced

Step 2)
Divide by gravity to get mass of object
2.6 N / 9.81 m/s^2 = .265kg <-- mass of object

Step 3)
Take that and divide by the density of water
.265kg / 1000kg/m^3 = 2.65E-4 m^3 <--equals the volume of the object
 
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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