Question

A lake contains water at a maximum depth of 237.3 meters. This water has a density of 989 kg/m3 and the acceleration due to gravity at this location is 9.806 m/s2. The air above the water has a barometric pressure of 29.83 in of Hg where the altitude correct for pressure is -1.87 in of Hg to get absolute pressure. What is the absolute pressure at the bottom of the lake?

Answer 1

Answer:690.21 mm of Hg

Explanation:

Given data

depth of lake$\left (h\right )$=237.3m

density of lake water$\left ( \rho\right )$=$989kg/m^3$

acceleration due to gravity$\left ( g\right )$=$9.806m/s^2$

air  above water has a barometric  pressure of 29.83in of Hg=711.2 mm of Hg

Altitude correct for pressure=1.87in of Hg=47.5 mm of Hg

Absolute pressure above water =711.2-47.5mm of Hg=663.7 mm of Hg

Absolute pressure at bottom of Lake=Pressure at surface level +$\left ( \rho \times g\times h\right )$

Absolute pressure at bottom of Lake=663.7+$\frac{989\times 9.81\273.3}{10^{5}}$

Absolute pressure at bottom of Lake=690.21 mm of Hg