A charge of magnitude $3e$ and mass $2m$ is moving in an electric field $\overrightarrow E .$ The acceleration imparted to the charge is
$2Ee/3m$
$3Ee/2m$
$2m/3Ee$
$3m/2Ee$
Which one of the following devices makes use of the electrons to strike certain substances to produce fluorescence
In an electron gun the control grid is given a negative potential relative to cathode in order to
What is value (magnitude) of electric field required for field emission ?
${O^{ + + }},\;{C^ + },\;H{e^{ + + }}$ and ${H^ + }$ ions are projected on the photographic plate with same velocity in a mass spectrograph. Which one will strike farthest
Explain emission of electron from metal. Define work function. Write its unit, work function of metal depend on which factors ?