Specific Gravity and Pressure in Flowing Pipe

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Maneuver1
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Homework Statement

The following question is from ExamKrackers Physics [an MCAT prep book].

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An ideal fluid with specific gravity of 1.0 is passed through a pipe. Along the length of the pipe shown above are attached 3 vertical pipes which are sealed off as shown above. If now a different ideal fluid with a specific gravity of 2.0 is passed through the pipe at the same volume flow rate the pressure at any point in the pipe would:

a. decrease by a factor of 2
b. remain the same
c. increase by a factor of 2
d. more information is required

Homework Equations



K = P + pgy + 1/2*pv^2

The Attempt at a Solution



Based on bernoulli's equation above if you increase rho, pressure would have to decrease since the terms of bernoulli's equation sum to a constant. The answer given by Examkracers is that [c] the pressure increases by a factor of 2. I can't seem to see why this would be true. Any help would be greatly appreciated.
 
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Welcome to PF!

Hi Maneuver1! Welcome to PF! :smile:

(have a rho: ρ and try using the X2 tag just above the Reply box :wink:)
Maneuver1 said:
Based on bernoulli's equation above if you increase rho, pressure would have to decrease since the terms of bernoulli's equation sum to a constant. The answer given by Examkracers is that [c] the pressure increases by a factor of 2.

I think you're both wrong …

Bernoulli's equation is constant along a streamline

unless you know something about the starting (or finishing) conditions, I don't see how you can say anything about the pressure :confused: