Q. 94.7( 6 Votes )

# The density of water at 4°C is supposed to be 1000 kg m^{–3}. Is it same at the sea level and at a high altitude?

Answer :

The density of water is related to temperature. At the temperature of 4°C the density of water is the highest. Atmospheric pressure is inversely proportional to altitude. So, when altitude increases, the atmospheric pressure decreases. According to the equation P=hρg, where ρ=density of fluid and P is the pressure of fluid, pressure depends on density. Therefore at 4°C, as the pressure is less, the water density at high altitude will be lower compared to sea level density.

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Show that moment of inertia of a solid body of any shape changes with temperature as I = I_{1}(1 + 2αθ), where I, is the moment of inertia at 0°C and α is the coefficient of linear expansion of the solid.

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