Formula of energy per unit weight

[foo9008]

Homework Statement

is the equation in the 3rd photo wrong ? since there are 2 exits , why shouldn't the eqaution become (P1 / y) + z + (8.33^2) / (2x9.81) = 0 + z +[ 2 (12^2) / (2x9.81) ] ?

Homework Equations

The Attempt at a Solution

 

[haruspex]

Bernoulli's equation is in respect of one streamline. A given streamline can only have one entry and one exit.

 

[foo9008]

Bernoulli's equation is in respect of one streamline. A given streamline can only have one entry and one exit.

but there are 2 exit, just consider 1 exit and ignore the another 1 ? how if the velocity at the 2 exit are different ?

 

[haruspex]

but there are 2 exit, just consider 1 exit and ignore the another 1 ? how if the velocity at the 2 exit are different ?

Bernoulli's equation is telling you they would be the same velocity. Consider two streamlines, one from the inlet to one outlet, and one to the other outlet. Same pressure difference, same height difference.

 

[foo9008]

Bernoulli's equation is telling you they would be the same velocity. Consider two streamlines, one from the inlet to one outlet, and one to the other outlet. Same pressure difference, same height difference.

how do you know that the difference in pressure are the same?

 

[haruspex]

how do you know that the difference in pressure are the same?

The third attachment says the pressure is atmospheric at both exits.