How Do You Calculate Pressure Drop in a Garden Hose?

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To calculate the pressure drop in a 28.0 m long garden hose with a diameter of 1.30 cm delivering water at a rate of 0.610 liters/s, Poiseuille's equation is applied. The relevant parameters include the viscosity of water at 1.003E-3 Pa*s, and the flow rate converted to cubic meters per second as 0.000610 m3/s. The initial calculation yielded a pressure drop of 27,400 Pa, but this was later determined to be incorrect. The discussion highlights the importance of correctly applying the formula and verifying calculations. Ultimately, the user resolved the issue independently.
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Homework Statement



A straight horizontal garden hose 28.0 m long with an interior diameter of 1.30 cm is used to deliver water at the rate of 0.610 liters/s. Estimate the pressure drop (in Pa) from one end of the hose to the other. The coefficient of viscosity for water is 1.003E-3 Pa*s.

Homework Equations





The Attempt at a Solution



Thought this was an easy problem, but can't figure out what I am doing wrong.

Given:
L=28.0m
d=0.013m ===> r=0.0065m
Q(Flow Rate)=0.610L/s... when you convert L - m3... 0.000610m3/s
viscosiy=1.003*10^-3 Pas

So, when you rearrange Poiseuille's equation for \DeltaP ...(P2-P1), you get;

(P2-P1)=8(Viscosity)(L)(Q)/piR^4

Ended up getting 27400Pa=(P2-P1).. I figured this was the pressure drop, and this was the way to do this problem but this answer is incorrect.

Help!
 
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Nevermind, got it!
 
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