# A weatherman carried an aneroid barometer from the groundfloor to his office atop a tower. On the ground level, the barometer read 30.150 in Hg absolute; topside it read 28.607 in hg absolute. Assume that the average atmospheric air density was 0.075lb/ft3, estimate the height of the building.

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A weatherman carried an aneroid barometer from the groundfloor to his office atop a tower. On the ground level, the barometer read 30.150 in Hg absolute; topside it read 28.607 in hg absolute. Assume that the average atmospheric air density was 0.075lb/ft3, estimate the height of the building.

2020-10-19
Let us consider the intial pressure at ground level is $$\displaystyle{P}_{{1}}$$
Let us consider the intial pressure at the top of the tower is $$\displaystyle{P}_{{2}}$$
Difference between the pressures at two places can be given $$\displaystyle{P}_{{1}}-{P}_{{2}}\rho{h}{g}$$
Therefore the height of the toweris given by
$$\displaystyle{h}={\frac{{{P}_{{1}}-{P}_{{2}}}}{{\rho{g}}}}$$
Where $$\displaystyle\rho$$ is the average atmospheric air density.
'g' is the accelaration due to gravity.
Substitute the above values in the formula to get the height of the tower.

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