# Tag Info

RPM is just another way to say ${min^{-1}}$ so to make your equations dimensionless while still using RPM you need to convert your other measurements using seconds to minutes. For the head coefficient $c_h=\dfrac{gH}{N^2D^2}$ this means you need to convert $g$ from $m.s^{-2}$ to $m.min^{-2}$ (in other words multiply by 3600) For the volume coefficient \$c_q= \...