The body weighs 100 N in air and 60 N in fresh water. Find its density.

To find the density of the taken body, we will use the equality: P1 – P2 = Fa = ρw * g * V = ρw * g * P1 / (g * ρx) = ρw * P1 / ρx, whence we express: ρx = ρw * P1 / ( P1 – P2).

Constants and variables: ρw – fresh water density (ρw = 1000 kg / m3); P1 – weight in air (P1 = 100 N); P2 – weight in water (P2 = 60 N).

Let’s calculate: ρx = ρw * Р1 / (P1 – P2) = 1000 * 100 / (100 – 60) = 2500 kg / m3.

Answer: The density of the body taken is 2500 kg / m3.



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