Question

A pneumatic displacement gage is to be used to measure displacements between 0.1 and 0.25 mm. The output of the device is a hypodermic needle having a diameter of 0.4 mm. The measurement is to be performed with an uncertainty of 25 nm. Specify values of the orifice diameter, upstream pressure, and allowable uncertainty in the pressure measurement to accomplish this objective.

Hint: If needed, the constants can be assumed appropriately yourself.

Answer 1