An ore sample weighs 17.50 n in air. when the sample is suspended by a light cord and totally immersed in water, the tension in the cord is 11.20 n. find the total volume and the density of the sample.

Volume of the sample: approximately .

Average density of the sample: approximately .

Assumption:

Explanation:

The size of the buoyant force is equal to .

That's also equal to the weight (weight, ) of water that the object displaces. To find the mass of water displaced from its weight, divide weight with .

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Assume that the density of water is . To the volume of water displaced from its mass, divide mass with density .

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Assume that the volume of the cord is negligible. Since the sample is fully-immersed in water, its volume should be the same as the volume of water it displaces.

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Average density is equal to mass over volume.

To find the mass of the sample from its weight, divide with .

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The volume of the sample is found in the previous part.

Divide mass with volume to find the average density.

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