Inside a cylindrical capacitor of inner radius a and outer radius b, an electron is projected from the surface of inner cylindrical shell perpendicular to it with an initial velocity. In the annular region between the two cylindrical shells a uniform magnetic induction B exist in direction parallel to the axis of capacitor. Find tbe maximum initial velocity with which tbe electron is to be projected so that it will not hit the outer shell.

Answer

`[(eB (b^(2) - a^(2)))/(2 mb)]`