List of top Physics Questions on Photoelectric Effect asked in NEET (UG)

If \(\phi\) is the work function of photosensitive material in eV and light of wavelength of numerical value \(\lambda = \frac{hc}{e}\) metre, is incident on it with energy above its threshold value at an instant then the maximum kinetic energy of the photo-electron ejected by it at that instant (Take \(h\)-Planck’s constant, \(c\)-velocity of light in free space) is (in SI units):

The power radiated by a black body is $P$ and it radiates maximum energy at wavelength, $\lambda_0$. If the temperature of the black body is now changed so that it radiates maximum energy at wavelength $\frac{3}{4} \lambda_0$ , the power radiated by it becomes $nP$. The value of $n$ is

The value of Planck's constant is

The cathode of a photoelectric cell is changed such that the work function changes from $W_1$ to $W_2 (W_2 > W_1).$ If the current before and after changes are $I_1$ and $I_2$, all other conditions remaining unchanged, then (assuming $h \upsilon > W_2$)

The momentum of a photon of an electromagnetic radiation is $3.3 \times 10^{-29}\, kg\, ms^{-1}.$ What is the frequency of the associated waves ? $[h=6.6 \times 10^{-34}\, Js\, ;\, c = 3 \times 10^8\, ms^{-1}]$