The principle that gas flow is proportional to the pressure drop ...

[ericka1]

The principle that gas flow is proportional to the pressure drop across a known resistance is used by which of the following devices?
 
  a. Turbine flowmeter c. Fleisch pneumo-tachograph
  b. Thermal flowmeter d. Ultrasonic pneu-motachograph

Question 2

Which type of flow-measuring device uses struts to create a partial obstruction to gas flow, caus-ing whirlpools to be produced when gas flows through it?
 
  a. Monel pneumo-tachograph c. Vortex ultrasonic flowmeter
  b. Ceramic pneumo-tachograph d. Variable-orifice pneumotachograph

[amynguyen1221]

Answer to Question 1

ANS: C
All pneumotachographs, except the ultrasonic pneumotachograph, operate on the principle that gas flow through them is proportional to the pressure drop that occurs as the gas flows across a known resistance.

Answer to Question 2

ANS: C
The vortex ultrasonic flowmeter uses struts to create a partial obstruction to gas flow. As gases flow past these struts, whirlpools (or vortices) are produced. The frequency at which these whirlpools are produced is related to gas flow through the struts.

[ericka1]

TYSM

[alexanderhamilton]

Thanks for the timely response, appreciate it