Tube speed
= Tube speed
{title2=$v_T$}
{wiki}
The tube speed combines sound and Alfvén speeds according to
$$
v_T^2=\frac{v_s^2v_A^2}{v_s^2+v_A^2}.
$$
It is smaller than both constituent speeds.
= Tube speed
{title2=$v_T$}
{wiki}
The tube speed combines sound and Alfvén speeds according to
$$
v_T^2=\frac{v_s^2v_A^2}{v_s^2+v_A^2}.
$$
It is smaller than both constituent speeds.