Troubleshooting Units in Energy Balance Problem

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The discussion centers on a homework problem involving energy balance in fluid dynamics, specifically calculating kinetic energy for water flowing through a nozzle. The user is confused about the conversion factor of 25037, which is used to convert kinetic energy from BTU/lbm to ft²/s². This conversion is necessary because the problem is presented in English units, which differ from the metric system where kinetic energy is typically expressed in Joules. The user acknowledges a lack of familiarity with English units and seeks clarification on the need for this conversion factor. Understanding this conversion is crucial for accurately solving the energy balance problem.
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I do not want to post the entire homework problem as I understand all of it except this one part.

The problem deals with energy balance and it states that water is flowing through a nozzle. (From a bigger cross sectional area to a smaller one.) I am trying to calculate the energy of the kinetic energy but my book does something weird to me.

The problem is in English units. (Very annoying!) The kinetic energy of a fluid would be..
\frac{1}{2}mv^2=[Btu]
So the specific energy should be..
\frac{1}{2}v^2=[\frac{Btu}{lbm}]

In the book they do the following..
(\frac{1}{2}v^2)(\frac{1[Btu/lbm]}{25037 [ft^2/s^2]})

That 25037 is throwing me for a loop. Why do I need this conversion? I thought KE was already in the correct units?

My assumption is that it is similar to metric units since KE is in Joules and normally you want it in KJ. Seems like I am just ignorant of English units. Can anyone shed some light on this?
 
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It's just a conversion factor.

1 \frac{BTU}{lbm} = 25037 \frac{ft^2}{s^2}

So they're converting from BTU/lbm to ft2/sec2 for whatever reason (no doubt made clear by what then follows).
 
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