Mechanical Engineering - Hydraulics and Fluid Mechanics - Discussion

The answer should be c high pressure.

For low pressure, simple piezometer is used although it is a part of a manometer it is not called as piezometer manometer it is called a simple piezometer.

The modification in the piezometer gives you tube manometer and a single column manometer which are used to measure moderate and high pressure and also have the name manometer.

So in the question you tube and single column is hidden or we can say silent so manometer should be taken as you tube and single column because they have name manometer.


Thanks.

@Gautam Sahni.

We can measure high pressure by piezometer but for this, we should have large piezometer (2 meters, 3 meters or more) to measure high pressure and it should be installed in the vertical direction so it is difficult to take a reading for us. So we don't use piezometer to measure high pressure. Mechanical gauge is used to measure high pressure.

So the answer to the above question is A&B.

I hope now it is clear.

In manometers there are different types of classification:

1. Simple Manometers:

A) Piezometer - Measures Low or moderate pressure.

B) U-Tube - Measures pressure at a point.

C) Single column Manometer - Measures pressure at a point (accurate).

2. Differential Manometers:

Measure pressure differences between a two point.

How can we judge that if manometer liquid has less specific gravity like oil, water then reading will be more for less pressure difference between ambient and manometer end.

If specific gravity is more less amount of change in reading so small tube is enough to measure large pressure but not as large as mechanical gauges.

My dear friends the manometer works on the principle of balancing the pressure by manometric fluid so if the pressure is low or moderate then the deflection detected would be very less & it may be possible that deflection will be negligible, so it is used to measure high pressure.

Manometers are devices in which columns of a suitable liquid are used to measure the difference in pressure between two points or between a certain point and the atmosphere.

So, option B is wrong. Atmospheric pressure is measured partially but not HIGH PRESSURE AS GIVEN.

If manometer is used to measure high pressure then why we use mechanical gauges like Bourdon pressure gauge. We generally use Bourdon pressure gauge in labs to measure high pressure.

So, guys, manometers are used to measuring low pressure or moderate pressure.

If high specific wt liquid is used in manometer like Hg difference of height in arms of manometer 760 mm will give 1 Kg/cm2. If water is used difference will be 13 times more. So I think it is used low pressure measurement.

Piezometer is use to measure low or Moderate pressure either Manometer is use to measure High pressure or pressure at a point.

Barometer is used to measure Atmospheric pressure.

It is correct.

Simple Manometer is used to measures low pressure because one of its ends is open to atmosphere, if liquid pressure is higher than atm pr then high-density liquid will fall from right limb.