# Bernoulli's pitot tube jet question

1. Sep 12, 2011

### louza8

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

The tip of the Pitot tube is at the top of the jet. Calculate the flowrate and the angle θ .

2. Relevant equations

3. The attempt at a solution
Please see attached images. 1 is the question and 1 is my attempted solution.

I think I perhaps have done the first part wrong where I calculate the horizontal component of the velocity. I assume the horizontal velocity remains constant throughout the trajectory, and that that the change in height z in the pitot tube is due to this velocity such that:

v=sqrt(2gz)

also, the lecturer has provided information that the fluid is water (density 1g/cm^3) and I haven't used this information hence my post here regarding my method.

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2. Sep 16, 2011

### rude man

I think everything you did was correct. I checked for the functioning of a pitot tube and your formula for vx corresponds to what they state. The density drops out both for vx and vy. Maybe you prof was alluding to the fact that the fluid from the spout and that in the manometer were the same substance. Had they not been, their relative densities would have come into play.

Good job!

BTW it's pretty obvious that vx stays constant, right? No different than throwing a ball in the air at an angle etc.

http://en.wikipedia.org/wiki/Pitot_tube

Last edited: Sep 16, 2011
3. Sep 16, 2011

### louza8

thanks for your time rude man