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Critical balance makes the nonlinear interaction time comparable to the wave period:An order-one interaction transfers energy in ${\tau }_l\sim {\tau }_{\mathrm{nl}}$, so constant energy flux gives $ϵ\sim v_A^3{d}_i{b}_l^3/l_{\perp }^2$. Thus the critically balanced electron-magnetohydrodynamic cascade hasFor the corresponding perpendicular magnetic energy spectrum, $\delta B_l^2\sim k_{\perp }{E}_B(k_{\perp })$ gives $E_B(k_{\perp })\propto k_{\perp }^{-7/3}$. The increasing ratio $l_{\parallel }/l_{\perp }\propto l_{\perp }^{-2/3}$ describes progressively more anisotropic fluctuations at smaller perpendicular scales, within the range in which the model and critical balance assumptions hold.