Linear velocity in terms of angular velocity $-E.$ By focusing on the meaning of $r,$ both regarding its magnitude and direction, show that it equals $v$ in Fig. $5\mathrm{.}6.$ Also prove that $v=r$ can be expressed as the determinant in Eqn. $(5\mathrm{.}25).$

Angular velocity and the curl$-$E$.$ Verify Ean