Wzór wirnika maszyny kretej 1,2:

Postac masowa:

1) lut∞=u(C2u − C1u) 2) $lut\infty = \frac{C2^{2} - C1^{2}}{2} - \frac{W1^{2} - W2^{2}}{2}$

Objetościowa:

1) put∞=ρu(C2u−C1u) 2) $put\infty = \rho\left( \frac{C2^{2} - C1^{2}}{2} - \frac{W1^{2} - W2^{2}}{2} \right)$

Ciężarowa:

$1)\ Hut\infty = \frac{1}{g}u\left( C2u - C1u \right)$ 2)$\ Hut\infty = \frac{1}{g}\left( \frac{C2^{2} - C1^{2}}{2} - \frac{W1^{2} - W2^{2}}{2} \right)$