A U-tube contains water and methylated spirit separated by mercury. The mercury columns in the two arms are in level with 10.0 cm of water in one arm and 12.5 cm of spirit in the other. What is the specific gravity of spirit?

Asked by Pragya Singh | 1 year ago |  74

##### Solution :-

Given:

Height of the spirit column, h1 = 12.5 cm = 0.125 m

Height of the water column, h2 = 10 cm = 0.1 m

Let, A and B be the points of contact between spirit and mercury and water and mercury, respectively.
P0 = Atmospheric pressure
ρ1 = Density of spirit
ρ2 = Density of water

Pressure a point A = P+ ρ1h 1g

Pressure at point B = P+ ρ2h 2g

We know pressure at B and D is the same so;

P+ ρ1h1g = P+ ρ2h 2g

$$\dfrac{ \rho _{ 1 } }{ \rho _{ 2 } } = \dfrac{ h _{ 2 } }{ h _{ 1 } } = \dfrac{ 10 }{ 12.5 }= 0.8$$

Therefore the specific gravity of water is 0.8.

Answered by Abhisek | 1 year ago

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