Calculate Pressure Gauge Reading in Wide Section of Pipe

AI Thread Summary
Water flows through a horizontal pipe that narrows from 10.2 cm to 4.89 cm, with a pressure gauge reading of 47.0 kPa in the narrow section. The discussion emphasizes using the conservation of mass to determine fluid speeds and applying Bernoulli's equation to find the pressure in the wider section. Initial attempts to calculate pressure using force and area were deemed incorrect. Participants clarified that force is not necessary for this problem. The correct approach involves focusing on fluid dynamics principles rather than force calculations.
brunettegurl
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Homework Statement



Water flows at 3.64 L/s through a horizontal pipe that narrows smoothly from 10.2 cm diameter to 4.89 cm diameter. A pressure gauge in the narrow section reads 47.0 kPa. What is the reading of a pressure gauge in the wide section?

Homework Equations



F=PA

P1+ \rhogh+0.5*\rhoV2=P2+\rhogh+o.5*\rhoV2

The Attempt at a Solution



so first thing i did was convert 3.64L/s to 3.64x10-3 m3/s
and then found the area of each part of the opening. since they tell me the gauge reading at the narrow end (4.89cm) i used F=PA to find the force. using this force and the area of the wide end (10.2cm) i got a P. this was wrong..can someone tell me what I'm doing wrong??
 
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Hi brunettegurl! :smile:

(have a rho: ρ :wink:)

I'm confused … what does force have to do with it? :confused:

Use conservation of mass to find the speeds, and then use Bernoulli's equation :smile:
 
thanks i realized that after i redid what i did
 

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