The power number Np (also known as Newton number) is a commonly-used dimensionless number relating the resistance force to the inertia force.
The power-number has different specifications according to the field of application. E.g., for stirrers the power number is defined as:
with
- P: power
- ρ: fluid density
- n: rotational speed
- d: diameter of stirrer
Famous quotes containing the words power and/or number:
“Hearing, seeing and understanding each other, humanity from one end of the earth to the other now lives simultaneously, omnipresent like a god thanks to its own creative ability. And, thanks to its victory over space and time, it would now be splendidly united for all time, if it were not confused again and again by that fatal delusion which causes humankind to keep on destroying this grandiose unity and to destroy itself with the same resources which gave it power over the elements.”
—Stefan Zweig (18811942)
“Computers are good at swift, accurate computation and at storing great masses of information. The brain, on the other hand, is not as efficient a number cruncher and its memory is often highly fallible; a basic inexactness is built into its design. The brain’s strong point is its flexibility. It is unsurpassed at making shrewd guesses and at grasping the total meaning of information presented to it.”
—Jeremy Campbell (b. 1931)