# physics pbs

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A bodybuilder is holding a 20-kg steel barbell above her head. How much force would she have to exert if the barbell were lifted underwater?

• physics pbs -

You will need to look up the density of steel.

The weight of the barbell under water will be
20 kg * g - V *(densityH2O)* g
V * g [densitysteel) - densityH2O)

The weight in water will be the weight in air (20 g = 196 Newtons) multiplied by [1 - (densityH2O/densitysteel)]

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