Rotating Sprayer

A sprayer consists of four bent pipes of length 2a for each pipe. The pipes can freely rotate about point O without friction.An ideal fluid of mass density ρ flows into the sprayer through point O from a large tank of pressure P (assume it's much larger than atmospheric pressure).
After a long time, the sprayer reaches a constant angular velocity, ω. Ignore gravity, energy lost, and turbulence of fluid.
Calculate ω!


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