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A 0.78-kg piece of wood floats in water but is found to sink in alcohol (SG=0.79), in which it has an apparent mass of 0.088 kg .

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What is the SG of the wood?

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Step 1:

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The weight of the wood is $\"\"$ .

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The specific gravity of alcohol is $\"\"$ .

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The apparent weight of the wood is $\"\"$ .

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The apparent weight of the wood $\"\"$ , where $\"\"$ is buoyant force.

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The buoyant force is $\"\"$ .

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$\"\"$

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$\"\"$ .

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The weight of the wood is $\"\"$ .

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Specific gravity of an object is the ratio of density of sample to density of reference substance.

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The specific gravity of alcohol is

\"\"

.

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\"\"

.

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The specific gravity of wood is

\"\"

.

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\"\"

. \ \

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Find the specific gravity of wood.

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Consider

\"\"

.

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\"\"

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Substitute $\"\"$ and $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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The specific gravity of wood is $\"\"$ .