4 ms·
Mach number is an odd example of a dimensionless number, especially with the example of measuring it in kph or mph (as opposed to being independent of altitude
by kevinpet 5y ago
Mach number is an odd example of a dimensionless number, especially with the example of measuring it in kph or mph (as opposed to being independent of altitude or temperature).
- oakwhiz 5y agoFunny, I was thinking the exact opposite. The Mach number has two velocities that cancel out, and velocity tends to be an easy concept to grasp, making it a textbook example of a dimensionless number. The part where Mach numbers are converted back to velocities requires you to input knowledge on the speed of sound, but there isn't a single answer for that unless you know the composition of the fluid, which is dependent on chemical composition, altitude and temperature. If you take a guess for that number, it's a unit conversion error rather than a variation in the dimensionless quantity itself.