An open-tube mercury manometer is used to measure the pressure in a gas tank. When the atmospheric pressure is 101,325 \(P_a\), what is the absolute pressure in \(P_a\) in the tank if the height of the mercury in the open tube is 25 cm higher. density of mercury = \(13600kg/m^3, g = 9.8m/s^2\)

A.

108,986 Pa

B.

165,238 Pa

C.

122,364 Pa

D.

134,645 Pa

Correct answer is D

density (ρ) = 13600 \(kgm^{-3}\); g =\(9.8 ms^{-2}\)

\(P_{atm}\) =101,325 Pa;  ρ=13600 \(kgm^{-3}\)


Pabs=\(P_{atm}\)+ρgh


⇒Pabs=101,325+13600 x 9.8 x 0.25
 

⇒Pabs=101,325+33320

⇒ Pabs=134,645Pa