Help using Bernoulli's equation

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SUMMARY

The forum discussion centers on applying Bernoulli's equation to determine the pressure at a pump given the flow conditions in a hose and nozzle system. The water flows at 0.61 m/s through a 3.0 cm diameter hose and exits through a 0.30 cm diameter nozzle, resulting in a calculated exit speed of 61 m/s. The user initially calculated the pressure at the pump as 1860314.95 atm, which is incorrect due to unit conversion errors. The correct approach requires converting pressure to metric (MKS) units for accurate calculations.

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  • Understanding of Bernoulli's equation and its components
  • Knowledge of fluid dynamics principles, specifically laminar flow
  • Familiarity with unit conversions, particularly from atm to metric units
  • Basic algebra skills for manipulating equations
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Homework Statement



Water flows at 0.61 m/s through a 3.0 cm diameter hose that terminates in a 0.30 cm diameter nozzle. Assume laminar non-viscous steady-state flow.

(a) At what speed does the water pass through the nozzle? (Correctly solved to be 61 m/s).

(b) If the pump at one end of the hose and the nozzle at the other end are at the same height, and if the pressure at the nozzle is 1 atm, what is the pressure at the pump in atm?


Homework Equations



P1 + .5p(v1)^2 = P2 + .5p(v2)^2

P1 = Looking for this
p = 1000 kg/m^3 ??
v1 = .61 m/s
v2 = 61 m/s
P2 = 1 atm


The Attempt at a Solution



I plugged in all known variables, but P1 ended up being a very large number (1860314.95 atm), and this was incorrect. I'm thinking that possibly the density that I'm using is incorrect. Can anyone see what I am doing incorrectly?
 
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Most of your quantities are in metric (MKS) units, so the pressure will have to be converted to those units first.
 
Thanks! I wasn't sure about those units either.
 

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