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Question
If water be used to construct a barometer, what would be the height of water column at standard atmospheric pressure (76 cm of mercury) ?
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Solution
Case: When water is used in a barometer instead of mercury
Pressure exerted by 76 cm of mercury column, P = 76 × 13.6 × g dyn/cm2
Density of water, \[\rho_w\] = 103 kg/m3
\[ \therefore 76 \times 13 . 6 \times g = h \times \rho_\text{w} \times g\]
\[ \Rightarrow \text{h} = \frac{76 \times 13 . 6}{1}\]
\[ \Rightarrow \text{ h } = 1033 . 6 \text{ cm }\]
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