A stick of $1 \,m$ is moving with velocity of $2.7 \times {10^8}m{s^{ - 1}}$. ........... $m$ is the apparent length of the stick $(c = 3 \times {10^8}m{s^{ - 1}})$
$10$
$0.22$
$0.44$
$2.4 $
Particle nature and wave nature of electromagnetic waves and electrons can be shown by
In Thomson spectrograph experiment, four positive ions $P,Q,R$ and $S$ are situated on $Y-X$ curve a shown in the figure
In an electron gun the control grid is given a negative potential relative to cathode in order to
$n$ Millikan oil drop experiment, a charged drop of mass $1.8 \times {10^{ - 14}}kg $ is stationary between its plates. The distance between its plates is $0.90 cm$ and potential difference is $2.0$ kilo volts. The number of electrons on the drop is
Who produced electromagnetic waves for the first time ?