An electron is travelling horizontally towards east. A magnetic field in vertically downward direction exerts a force on the electron along

A charged particle of mass $m$ and charge $q$ travels on a circular path of radius $r$ that is perpendicular to a magnetic field $B$. The time taken by the particle to complete one revolution is

Fill the blank :

$(i)$ Static charge produces ...... field around it.(Electric, Magnetic)

$(ii)$ Moving charge produces ...... field around it.

A charge $q$ is moving in a magnetic field then the magnetic force does not depend upon

A particle of mass $m = 1.67 \times 10^{-27}\, kg$ and charge $q = 1.6 \times 10^{-19} \, C$ enters a region of uniform magnetic field of strength $1$ $tesla$ along the direction shown in the figure. the particle leaves the magnetic field at point $D,$ then the distance $CD$ is :-

A proton and a deutron ( $\mathrm{q}=+\mathrm{e}, m=2.0 \mathrm{u})$ having same kinetic energies enter a region of uniform magnetic field $\vec{B}$, moving perpendicular to $\vec{B}$. The ratio of the radius $r_d$ of deutron path to the radius $r_p$ of the proton path is: