Archimedes problem? density's of objects in liquids

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The discussion focuses on calculating the relative density of a solid and oil based on their weights in air, water, and oil. The solid weighs 260N in air, 240N in water, and 250N in oil, leading to the conclusion that it displaces 20N of water, equating to a volume of 2040.8 cm³. The mass of the solid is calculated as 26.5 kg, resulting in a density of approximately 0.01299 kg/cm³. To find the density of the oil, the same method used for the solid can be applied, utilizing the known volume and mass of the solid. The discussion emphasizes the importance of expressing weight in terms of density and volume for clarity in calculations.
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A solid weights 260N in air, 240N in water of a fluid density 1000kg/m^3, and 250N in oil

Determine the relative density of the solid and of the oil

I think I have already worked out the density of the solid:

Weight of water displaced = 260N - 240N = 20N

20N / 9.8 = 2.0408kg

Water density = 1kg per litre, so there is 2.0408 litres or 2040.8 cm^3

Mass of solid = 260N / 9.81 = 26.5kg

Mass/ Vol = Density = 26.5 / 2040.8 = 0.01299 kg/cm^3

If this is correct so far, how would I go about working the density of the oil, and are these figures measures of "relative density", which I understand to just be a comparison to the density of water?

Thank you!
 
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You're doing fine, but I would suggest that you try to do things symbolically instead of calculating every step. (You'll find it much easier to get your answer.)

How would you express the weight of the solid (or the fluids) in terms of density and volume?
 
What you have seems reasonable to me.
To work the oil, you do the same thing you did above, only now you know volume and mass of the solid.
 
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