Pressure Difference: Is the Solution Wrong?

[foo9008]

Homework Statement

is the solution given wrong ? from the bernoulli's equation , (PA-PB) / ρg = hf + ZB - ZA , am i right ? P/s : the Velocity at A and B are the same , so they cancel each other ... but in the solution , the author gave (PA-PB) / ρg = hf + ZA - ZB which is 18.27 +40 , IMO , it should be 18.27-40 , am i right ?

Homework Equations

The Attempt at a Solution

 

[Chestermiller]

Check your algebra.

 

[foo9008]

ya , what's wrong with it ?

 

[foo9008]

Check your algebra.

the question gave point A is 40m higher than B ...

 

[Chestermiller]

Yes. I agree with you.

 

[foo9008]

Yes. I agree with you.

since 18.27 - 40 has negative value , so the water should flow from B to A ?

 

[Chestermiller]

since 18.27 - 40 has negative value , so the water should flow from B to A ?

They probably meant to say that B is higher than A.

By the way, did you check the Reynolds number to see if the flow really would be laminar?