[shaw600]

Hi

I have a theory question that I hope you can help me with.

I'm going through the derivation of the major and minor system loss in natural ventilation and I have the major and minor losses in terms of the density:



However, when I look into these I find them in terms of gravitational acceleration:



How do you switch from one to the other?

The only way I have been able to find to do this is by using the specific weight:



But as this is not in the original equation, has it been assumed negligible as it is so small, therefore making: density = 1 / g

Here are links to the pages I used on EngineeringToolbox:
Natural Ventilation: http://www.engineeringtoolbox.com/na...ion-d_122.html
Minor Losses: http://www.engineeringtoolbox.com/mi...pes-d_626.html
Specific Weight: http://www.engineeringtoolbox.com/de...ity-d_290.html

I hope you can help.