question_answer

A proton of mass \[M=1.67\times {{10}^{-27}}kg\]moves uniformly in a space where there are uniform, mutually perpendicular electric and magnetic fields with \[{{E}_{z}}=4.5\times {{10}^{4}}\,\text{V}\,{{\text{m}}^{-1}}\]and \[{{B}_{x}}=40\text{mT}\]at an angle \[\phi =60{}^\circ \]with the x-axis in the xy- plane. The pitch of the trajectory after the electric field is switched off is ___ m.

Answer:

1.06