A source $S_1$ is producing, $10^{15}$ photons per second of wavelength $5000 \;\mathring A.$ Another source $S_2$ is producing $1.02 \times 10^{15}$ photons per second of wavelength $5100\;\mathring A$. Then, $($ power of $S_2)/$ $($ power of $S_1)$ is equal to
$1$
$1.02$
$1.04$
$0.98$
The momentum of a photon with energy $20\, eV$ is
A photon of $1.7 \times {10^{ - 13}}$ Joules is absorbed by a material under special circumstances. The correct statement is
Photo-electric effect can be explained by
An AIR station is broadcasting the waves of wavelength $300$ metres. If the radiating power of the transmitter is $10 kW$, then the number of photons radiated per second is