question_answer

The column of mercury in a barometer is 76 cm Hg. Calculate the atmospheric pressure if the density of mercury \[=\text{ }13600\text{ }kgn{{r}^{3}}\]. (Take \[g=10\text{ }m{{s}^{-2}}\])

Answer:

Atmospheric pressure = Pressure of mercury column of height 76 cm. \[h=76\text{ }cm=0.76\text{ }m\] \[d=13600\text{ }kg{{m}^{3}}\] \[g=10\text{ }m{{s}^{2}}\] \[P=hdg\] \[=0.76\times 13600\times 10\text{ }P\] \[=1.03\times {{10}^{5}}P\] Therefore, the atmospheric pressure is \[1.03\times {{10}^{5}}P\]