τ=Iα\tau=\frac{I}{\alpha}τ=αI
τ=Iα\tau=\sqrt{\mathrm{I} \alpha}τ=Iα
τ=I2α\tau=I^{2} \alphaτ=I2α
τ=Iα\tau=\mathrm{I} \alphaτ=Iα