Question

In the U tube manometer, if we use water as the liquid instead of mercury, you can get the height difference by doing which one of the following to an equivalent mercury expression for obtaining the pressure.
A.Multiplying by 13.6
B.Subtracting 13.6
C.Adding 13.6
D.Dividing by 13.6

Answer 1

Hint:We can say that the manometer is a wet meter that means the fluid whose pressure is being determined is brought in contact with another fluid. We can use mercury because it contains high density and so the manometer size is minimised. When we compare mercury to water, a much smaller column of mercury is needed to measure pressure

Complete step by step answer:U tube manometer has a U shaped tube in which the manometric liquid is filled. We can use a manometer to determine the unknown pressure by the acceleration due to gravity and balancing gravity force.
The manometer contains a steel, brass and aluminum material. It has a glass tube which is made up of pyrex glass. The graduations are marked on the tube in terms of mm or in certain conditions it is graduated in kiloPascal. We can calculate the pressure using the formula,
$P = \rho gh$
Here, $\rho $ is the density.
G is the acceleration due gravity and h is the height difference.
P is the pressure
We could obtain the pressure by multiplying the difference in weight along with the density and acceleration due to gravity. We can
We know that the density of water is 1g/mL and the density of mercury is 13.6 g/mL.
In the U tube manometer, if we use water as the liquid rather than mercury, we could obtain the difference in height by dividing by 13.6 to an equivalent mercury expression for getting the pressure.
Therefore, Option (D) is correct.


Note:There are some advantages and disadvantages in the U-tube manometer. Some of the advantages include,
-Low cost
-Simple construction
-Could be used to determine other process variables
-Sensitive and accurate.
Some of the disadvantages include,
-Fragile construction
-Sensitivity to changes in temperature.