Question

In the inclined manometer shown in the figure below, the reservoir is large. Its surface may be assumed to remain at a fixed elevation. A is connected to a gas pipeline and the deflection noted on the inclined glass tube is 100mm Assuming $\theta ={30}^{\circ }$ and the manometric fluid as oil with specific gravity of 0.86, the pressure at A is

• A. 43 mm water (vacuum)
• B. 43 mm water
• C. 86 mm water
• D. 100 mm water

Answer 1

The correct option is B 43 mm water

Total pressure at A will be equal to the pressure at the surface of manometric fluid because above the surface, the gas pipeline is connected.

$\therefore PreassureatA=100sin{30}^{\circ }mmofoil=50mmofoil$

We know that

$S_1{h}_1=S_2{h}_2$

$\Rightarrow 0.86\times 50=1\times h_2$

$\Rightarrow h_2=43mmofwater$