When green light is incident on the surface of metal, it emits photo-electrons but there is no such emission with yellow colour light. Which one of the colour can produce emission of photo-electrons
Orange
Red
Indigo
None of the above
A small object at rest, absorbs a light pulse of power $20\,mW$ and duration $300\,ns$. Assuming speed of light as $3 \times 10^8\,m / s$. the momentum of the object becomes equal to $.........\times 10^{-17} kg\,m / s$
The frequency of a photon, having energy $100eV$ is$(h = 6.6\,{10^{ - 34}}\,J{\rm{ - }}sec)$
According to Einstein's photoelectric equation, the graph between the kinetic energy of photoelectrons ejected and the frequency of incident radiation is
Light of intensity $10^{-5}\; W m ^{-2}$ falls on a sodium photo-cell of surface area $2 \;cm ^{2}$. Assuming that the top $5$ layers of sodium absorb the incident energy, estimate time required for photoelectric emission in the wave-picture of radiation. The work function for the metal is given to be about $ 2\; eV$. What is the implication of your answer?
If the total energy transferred to a surface in time $t$ is $6.48 \times 10^5 \mathrm{~J}$, then the magnitude of the total momentum delivered to this surface for complete absorption will be :