1. The problem statement, all variables and given/known data so I have been working on this problem : Diameter1 at wide end: 8cm || V1 = 1.56m/s Diameter2 at narrow end: 3cm || V2 = 11.094m/s Force exerted on plate = 87N Find the manometer reading Picture below: 2. Relevant equations P1+(1/2 ρv1^2)=P2+(1/2 ρv2^2) 1 − 2 = (2 −1)ℎ 3. The attempt at a solution I know that due to Bernoulli's Equation the pressure where velocity is at 11.094m/s is much lower than at the other end. This can also be seen from the Mercury(Hg) level. I have take P2 as being 0 because it is open to the atmosphere -- I am unsure whether this should be taken as 0 or 1. I have used the following equation to work out P1 : P1+(1/2 ρv1^2)=P2+(1/2 ρv2^2) and I end up with P1 = 4.5581(atm??) Can I use : 1 − 2 = (2 −1)ℎ in order to find the height ? Or is thus equation only valid for a differential manometer that has a constant cross sectional area ? I am still unsure how to proceed in this case. Any help or tips would be appreciated.