Calculating Volume Using Archimedes' Principle

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To calculate the volume of the object using Archimedes' Principle, the apparent weights in ethyl alcohol and water are compared. The equations for apparent weight in each liquid are established, factoring in the densities of ethyl alcohol and water. The relationship between the apparent weights leads to the conclusion that the ratio of the weights can be used to find the ratio of the densities. The user expresses difficulty in isolating the volume due to the presence of gravity in both equations. The discussion emphasizes the need for known densities of the liquids to proceed with the calculations.
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An object is solid throuhgout. When the object is completely submerged in ethyl alcohol, its apparent weight is 15.2N. When completely submerged in water, its apparent weight is 13.7N. What is the volume of the object?

This is my attempt:

Weight of object in ethyl alcohol [Woe]= (density of alchohol[de])(volume of object)(gravity)

Weight of object in water[Wow] = (densityof water[dw])(volume of object)(gravity)

therefore:

Woe/de = Wow/dw

Woe/Wow = de/dw
15.2/13.7 = de/dw

but this is where i get stuck..because both the equations have volume and gravity they just cancel and i can't solve for either of the densities...

thanks for any hints.. :confused:
 
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Apparent weight = real weight - buoyant force

Set up two equations, one for each liquid, and compare. You'll need the density of each liquid---look them up.
 
thank you :)
 
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