The liquid used in manometers should have
A. Low density
B. High density
C. Low surface tension
D. High surface tension
Answer: Option B
Solution (By Examveda Team)
Manometers are devices used for measuring pressure, typically in fluids. The liquid used in manometers should have high density.This is because higher density liquids are less affected by small changes in pressure, providing more accurate measurements.
Option A:
Low densityLow density liquids would be more sensitive to pressure changes, which could lead to less accurate readings.
Option C:
Low surface tensionSurface tension is not a critical factor in the selection of the liquid for a manometer. It doesn't directly impact the accuracy of pressure measurements.
Option D:
High surface tensionHigh surface tension liquids tend to form menisci in narrow tubes, which could affect the accuracy of pressure measurements in a manometer.
Therefore, the correct answer is option B:
High density.

The liquid used in manometers should have a high density so that the height of the column can be reduced. Because the manometers are used for high-pressure measurement, so it is important to make the column height in a practical limit.
In most cases, for gauge pressure measurements, mercury is widely used as manometric fluid because it has non-evaporating quality under normal conditions, sharp meniscus and stable density. For some pressure differences and low-level vacuum, water can be considered as working fluid in the manometer.
Important Points:
Manometric fluid should have low surface density so to have higher accuracy in the reading.
∴ Low surface tension is one of the desirable property but the most important property is the property of being highly densified.
Confusion Point:
Some students have found high surface tension as a correct option for the given question, but it is incorrect as it will reduce the efficiency of the manometer.
Answer = B
Because Should have high density to decrease the column height and due to which we can measure more range of pressure.
Answer : D
Because it should be non wetting. hence surface tension force should be more than adhesion force to make all particles intact. in case of mercury....
Low surface tension and high density.
Answer should be option A
High density is preferred as it will reduce the length of the column required to balance the pressure.