An electron and a proton each travel with equal speeds around circular orbits in the same uniform magnetic field as indicated (not to scale) in figure. The field is into the page on the diagram. The electron travels …….. around the ……..circle and the proton travels ……..around the……..circle.

$r=\frac{mv}{qB} \Rightarrow r\propto m$ (for v same for both sense and q,B are same)

direction of motion is given by Fleming's left hand rule

$$\begin{gathered} \mathit{C}\mathit{a}\mathit{s}\mathit{e}\mathbf{ }\mathbf{-}\mathbf{1} \\ field into the plane of paper \\ Magnetic force is towards centre \\ electron revolves in clockwise so current is in anticlockwise \\ \mathit{C}\mathit{a}\mathit{s}\mathit{e}\mathbf{ }\mathbf{-}\mathbf{2} \\ field into the plane of paper \\ Magnetic force is towards centre \\ Proton revolves in clockwise so current is in clockwise \end{gathered}$$