Magnetohydrodynamic shear work
= Magnetohydrodynamic shear work
{title2=$S=a(B_xB_y/\mu_0-\rho v_xv_y)$}
The <energy> of the residual flow and <magnetic field> in a maintained <shear flow> has source $S=-aT_{xy}$, where $T_{xy}=\rho v_xv_y-B_xB_y/\mu_0$. The kinetic and magnetic <stresses> can exchange <energy> with the imposed background. The source vanishes when their off-diagonal contributions cancel.