A charged particle is projected in a region of space where both electric field $\overrightarrow{\mathrm{E}}$ and magnetic field $\overrightarrow{\mathrm{B}}$ exist. Then speed of the particle

Magnetic force $\overrightarrow{{\mathrm{F}}_{\mathrm{B}}}$ acting on the particle does not perform any work on the particle as it is always perpendicular to the direction of motion. But electric force $\overrightarrow{{\mathrm{F}}_{\mathrm{E}}}=\mathrm{Q}\overrightarrow{\mathrm{E}}$ does work on the particle, except in the case when $\overrightarrow{\mathrm{E}} \mathrm{is} \mathrm{perpendicular} \mathrm{to} \overrightarrow{\mathrm{B}}$  and $\mathrm{v}=\frac{\mathrm{E}}{\mathrm{B}}$ and $\overrightarrow{\mathrm{v}}$ is perpendicular to both $\overrightarrow{\mathrm{E}} \mathrm{and} \overrightarrow{\mathrm{B}}$