# Specific Gravity and Pressure in Flowing Pipe

1. Jun 6, 2010

### Maneuver1

1. The problem statement, all variables and given/known data

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

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

2. Relevant equations

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

3. 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.

Last edited: Jun 6, 2010
2. Jun 6, 2010

### tiny-tim

Welcome to PF!

Hi Maneuver1! Welcome to PF!

(have a rho: ρ and try using the X2 tag just above the Reply box )
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