This document discusses different types of pressure measuring devices, including those that measure gauge pressure and absolute pressure. It describes several specific devices: 1) Barometers measure gauge pressure using a mercury-filled tube, with standard atmospheric pressure retaining the mercury at 760mmHg. 2) Manometers can be piezometers in an L-shape or U-shape, measuring the fluid height change in the tube relative to atmospheric pressure. 3) Differential manometers measure the absolute pressure difference between two connected fluid tanks, using the movement of a third reference fluid in the tube.

1. ABU-ZAR
YAWAR MUNIR
ANAS ALAM
SAQIB RAZA

2. NAME:YAWAR MUNIR CLASS NO:16
SECTION:A

3. PRESSURE MEASURING
DEVICES,ITS
TYPES,WORKING AND
PRINCIPLE:
• TYPES:
1-BASED ON MEASUREMENT OF GAGE
PRESSURE
2-BASED ON MEASUREMENT OF ABSOLUTE
PRESSURE

4. 1-BASED ON GAGE PRESSURE:
a-barometer
b-manometers
1b-peizometer
2b-u--shaped manometer
a-BAROMETER:
it was invented byTorcelli in
1634..it measures gauge pressure...with mercury
having standard value of 760mmHg pressure...all
other liquids pressure is determined

5. • WORKING:
To find pressure mercury is
taken in a tube with no air in it,it is
inverted in a tub of mercury,where
atmospheric pressure forces the mercury
level to retain it self at the level of
760mmHg after its falling
PRINCIPLE:
it is based on atmospheric
pressure that acts on tub and retains
mercury in tube

6. 1b-PEIZOMETER:
it is a
manometer...which is a simple one
also,fluid whose pressure is to be
measured is taken in a tank and
connected with a tube of height..which is
L in shape
PRINCIPLE:
it is that it depends upon

7. • WORKING:
fluid whose pressure is to
measured is poured in peizometer,through
the rise of height in tube,pressure is
measured,which is its drawback also that it
can't measure -ive pressure
2b-U SHAPED PIEZOMETER:
it is u in
shape.

8. • PRINCIPLE:
its principle is based on
atmospheric pressure...if pressure of
liquid is high..then it will show +ive
pressure but if not then it will show -ive
pressure
WORKING:
its working is same but
difference is that there will be -ive
pressure present which is not available in
L shaped piezometer which is due to

9. a-barometer 2b-U & L manometer

10. BASED ON ABSOLUTE PRESSURE:
a-differential manometer:
its structure is
different in this manner that both ends of
this manometer are connected to fluids
tanks whose pressure are to be
measured,pressure calculated is actually
compared to value of zero

11. PRINCIPLE:
it depends upon internal
pressure of both fluids contained in tube,not
atmospheric or gage pressure
WORKING:
Three fluids are contained in a
vessel tube,two whose pressure is to be
measured,one taken as a standard whose
movement will show pressure i.e whose
pressure is greator,phenomena is known as
pressure difference

12. a-differential
manometer