Manometer Example

[@IamChandEvil]

For the students who can't understand. He's taken a reference point where the pressures are equal at Hb distance into the water (depth).

[@lofiifishstudio7818]

@ 4:40 why does mercury should be negative? if the pressure is greater towards b, does it have any changes in the formula?

[@markbenn1907]

Thanks for your work. These are a little tricky but you explained very well.

[@ninawilliams1845]

Finally a native English speaker that explains well I love you

[@toose8388]

I don't get when you say that it doesn't matter whether you choose ha to be higher or hb. If you change it to the other way around (hb < ha, 0.5 ft of mercury now on the right side), then again starting from pipe B you get:
Pa = Pb + rho_h2o*g*hb + rho_me*g*0.5 - rho_h2o*g*ha
Substituting ha - hb = 0.5 ft:
Pa = Pb - rho_h2o*g*0.5 + rho_me*g*0.5 = 0.5*g*(rho_me - rho_h2o)
So this time the pressure of pipe a is higher than that of pipe b. In fact , it seems to me that this distinction (whether the mercury level is higher on the A side or B side) is exactly what tells us which pressure is highest. In that case, it seems silly that the problem would not specify where this height difference falls, unless it only wants the absolute value of (Pa - Pb).

[@marygrethelatun831]

Thank you for this video. It's just what I needed.
Very clear and well explained.
Good job 👍

[@vaibhavgrover3167]

i dont get where the negative comes from
isnt pressure a scalar quantity

[@quintinadossantos8194]

Would Pa-Pb not be equal to -1471 Pascals, instead of -18.76 kPa?
¿Pa-Pb no sería igual a -1471 Pascales, en vez de -18,76 kPa?

[@21mejia25]

Awesome, thank you!

[@subodhsharma4836]

It's amazing

[@manuele.morillo2204]

How can you tell if the difference of height between A and B is .5? You can't just look at the drawing.

[@LearnChemE]

It is given in the problem statement.

[@manuele.morillo2204]

+LearnChemE Thanks for the quick reply!

[@hugos408]

Nice!

[@maryamalharithi1533]

Ima fail physics