Relative orientation of the gas velocity and magnetic fields as a function of total gas density for our fiducial CHEM_MHD simulation at t = 186 Myr. Colours indicate the angle |cos α| defined by Eq. (19). Each slice at fixed n is normalised separately for improved clarity. The black solid line shows the average value of cos α at the given density while the dotted one shows the median instead. If the orientation of v with respect to В were completely random (in the solid angle), the distribution would be uniform and the black lines would be horizontal at a value |cos α| = 0.5. The plot shows that the velocity and magnetic fields become progressively more random as we move to higher densities.