How are pressure gradients measured?

Question

The question that I have to answer in an essay is: Describe how pressure gradients are measured.

Answer 1

In general, pressure gradients are measured by transducers which convert the pressure into a signal that can be read.  The transducers are typically stationary, and detect the changes in pressure as the medium moves past.

One example is a barometer.  This sits in one spot and detects the air pressure above it.  The direction of pressure change is inferred over time by watching the readings change.

Another example is a sphygmomanometer which measures blood pressure.  This is an inflatable cuff that closes off the blood vessels of the arm.  The user then listens with a stethoscope as the inflation is released to hear when the vessel opens again and allows blood to pass.  The two numbers, the systolic and diastolic pressures, are the two ends of the pressure gradient in the brachial artery.

A third example is a sound pressure microphone, for use in air or water.

Probably for your essay, you can look up how a barometer works and describe that.

Hope this helps.