Cathode rays enter into a uniform magnetic field perpendicular to the direction of the field. In the magnetic field their path will be
Straight line
Circle
Parabolic
Ellipse
${O^{ + + }},\;{C^ + },\;H{e^{ + + }}$ and ${H^ + }$ ions are projected on the photographic plate with same velocity in a mass spectrograph. Which one will strike farthest
An electron is moving in electric field and magnetic field it will gain energy from
The colour of the positive column in a gas discharge tube depends on
A narrow electron beam passes undeviated through an electric field $E = 3 \times {10^4}volt/m$ and an overlapping magnetic field $B = 2 \times {10^{ - 3}}Weber/{m^2}$. If electric field and magnetic field are mutually perpendicular. The speed of the electrons is
A charge of magnitude $3e$ and mass $2m$ is moving in an electric field $\overrightarrow E .$ The acceleration imparted to the charge is