Help using Bernoulli's equation

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The discussion revolves around applying Bernoulli's equation to a fluid dynamics problem involving water flow through a hose and nozzle. The correct speed of water passing through the nozzle is calculated to be 61 m/s. The user is attempting to find the pressure at the pump using the equation P1 + 0.5p(v1)^2 = P2 + 0.5p(v2)^2 but is encountering an incorrect value of 1860314.95 atm for P1. The issue is identified as a potential unit conversion problem, specifically regarding the pressure units, which need to be in metric (MKS) units for accurate calculations. Proper unit conversion is crucial for solving the problem correctly.
lilmul123
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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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