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Unit name

Unit name

Unit name

(OP)
Hi,   in a formula I found a number with following dimension (lb sec2/in4). Anybody know the name of that unit.
I found that that dimension come from density divided by gravitation.

thx

RE: Unit name

I think that I got your answer.  It appears to part of the  Bernouilli's energy equation $DP+$VDV+$DZ=0 (WHERE $ IS AN INTEGRAL SIGN) applied in fluid dynamics.  
The unit that you showed is derived as follows:
 









I think that the units you are questioning deal w/Bernouilli's equation $dp+$vdv+$dz where $ is an integral.
The unit is derived from the following:
     Pressure(lbf/in2)/(DENSITY(lbm/in2)/Gc(386.4 lbm-in2/lbf-sec2)).
Be carefull to know the differences between lb,lbf,lbm.
When I graduated in 1971 units were primarily expressed in the English system this is why you may not have been familiar with this form if you graduated later on using the metric units.
Just to let you know about the relationship between lb,lbf & lbm remember Newton law F=ma  
              F(lb)= m(slugs)*a(ft/sec2 or in/sec2)

                      m(lbm)*a(ft/sec2 or in/sec2)
             F(lbf)=  ---------------------------
                           Gc(=32.2lbm-ft/lbf-sec2  
                               or 386lbm-in/lbf-sec2)

RE: Unit name

Sorry my message got chopped up, I thought that I had lost my first paragraph so I retyped it in a shorter version-- but I think that you will still get the idea.

RE: Unit name

(OP)
Thanks for the explanation.  I get it now.

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