A cube of edge 20 cm floats on a liquid with 5 cm of its height projecting above the liquid surface. If the liquid density is 0.8 g/cc, find the mass of the cube.

4.2 kg
4.8 kg
5 kg
5.2 kg

Correct answer: 4.8 kg

Solution

Submerged depth = 15 cm. Submerged volume = 20*20*15 = 6000 cm³. Mass of cube = mass of displaced liquid = 6000 * 0.8 = 4800 g = 4.8 kg.

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