Force applied to simple hand pump and resulting PSI

[fred_1985]

I hope I am asking this in the right forum.

Lets say you have a simple hand pump, similar to a bicycle pump, and you exert X amount of force on the handle. How do you calculate the resulting air pressure it creates out of the small valve at the end?

Obviously friction between the O-ring and inner wall of the pump is going to come into play, but a rough estimate would do.

Thanks.

 

[russ_watters]

Pressure is force divided by area. Force on the handle, cross sectional area of the piston.