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**[SOLVED] Help with a pipe, water, continuity and Bernoullie**

## Homework Statement

At one point in a pipeline the water's speed is: 3.0 m/s,

the gauge pressure is: 5.0*10^4.

Find the gauge pressure at a second point in the line, 11m lower than the first, if the pipe diameter at the second point is twice that at the first.

## Homework Equations

Bernoullies Equation: P1 + density*g*y1 + 0.5*density*v1^2 = P2 + density*g*y2 + 0.5*density*v2^2

Continuity Equation: A1V1 = A2V2

## The Attempt at a Solution

I work out the speed of v2 using continuity, with area-1 being pi*r^2, Area-2 being pi*4r^2,

This makes the speed 3/4 m/s

I themn put all known variables into Bernoullies equation, which gives me a negative pressure! (-53581.25) this cannot be right?

Any Ideas/Suggestions

TFM