AutoQuiz is edited by Joel Don, ISA's social media community manager.
This automation industry quiz question comes from the ISA Certified Control Systems Technician (CCST) program. Certified Control System Technicians calibrate, document, troubleshoot, and repair/replace instrumentation for systems that measure and control level, temperature, pressure, flow, and other process variables. Click this link for more information about the CCST program.
a) viscosity
b) pressure
c) friction factor
d) temperature
e) none of the above
The Reynolds Number for a flowing fluid can be generalized as the ratio of kinetic (or inertial) forces divided by viscous forces. Although friction factor and temperature do affect inertial forces and viscosity to some degree, and therefore, Reynolds number, viscosity has the most direct effect upon the value of the Reynolds Number.
The correct answer is A, "viscosity."
Reference: Goettsche, L.D. (Editor), Maintenance of Instruments and Systems, 2nd Edition
About the Editor
Joel Don is the community manager for ISA and is an independent content marketing, social media and public relations consultant. Prior to his work in marketing and PR, Joel served as an editor for regional newspapers and national magazines throughout the U.S. He earned a master's degree from the Medill School at Northwestern University with a focus on science, engineering and biomedical marketing communications, and a bachelor of science degree from UC San Diego.