A barometer kept in an elevator accelerating upwards reads 76 cm of mercury. If the elevator is accelerating upwards at 4.5`ms^(-2)`. Find the air pressure in the elevator in cm of mercury.
Density of mercury `=13.6xx10^(3)kgm^(-3)` [Take `g=9.8m//s^(2)`].

Explanation

When a elevator moves upwards with acceleration a then,
`{:("Net"),("acceleration"):}}=g+a`
pressure `=hrho(g+a)`
`=0.76xx(13.6xx10^3)xx(9.8+4.5)`
`=(0.76xx13.6xx10^(3)xx14.3)/(9.8xx(13.6xx10^(3)))` m of Hg
`=1.11` m of Hg `=111` cm of Hg