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## Homework Statement

Determine y

_{2}(ft)and v

_{2}(ft/s) using the momentum principle assume widths are the same at 1 and 2

## Homework Equations

from what i remember in my past fluids class, the momentum equation is:

Force = Qv

_{out}- Qv

_{in}assuming same density and direction

However in my lecture the professor provided another equation

but when i work out the units in this equation left side yields Force and right side is pressure (force/area)

did my professor forget to multiply each pressure with its respective Area? P

_{1}A

_{1}?

## The Attempt at a Solution

using ##\rho####\beta##QV

_{2}- ##\rho####\beta##QV

_{1}= P

_{1}A

_{1}-P

_{2}A

_{2}

assume both ##\beta##'s = 1

assume width = 1

using continuity equation Q = V

_{1}A

_{1}= V

_{2}A

_{2}= (4.55)(1)(8.55)=y

_{2}(1)V

_{2}

##\rho##(4.55)(1)(8.55)(V

_{2}- V

_{1})= P

_{1}(4.55)(1)-P

_{2}y

_{2}(1)

##\rho##38.9(V

_{2}- 8.55)= P

_{1}4.55-P

_{2}y

_{2}

I am stuck