Every question from past board papers on Einstein's photoelectric equation, particle nature of light, newest paper first. Open any question for its full worked answer.
If \(c\) is the velocity of light in free space, the correct statements about photon among the following are :
A. The energy of a photon is \(E=h\nu\).
B. The velocity of a photon is \(c\).
C. The momentum of a photon, \(p=\frac{h\nu}{c}\).
D. In a photon-electron collision, both total energy and total momentum are conserved.
E. Photon possesses positive charge.
Choose the correct answer from the options given below :
The minimum wavelength of \(X\)-rays produced by an electron accelerated through a potential difference of \(V\) volts is proportional to:
When two monochromatic lights of frequency, \(\nu\) and \(\frac{\nu}{2}\) are incident on a photoelectric metal, their stopping potential becomes \(\frac{V_s}{2}\) and \(V_s\) respectively. The threshold frequency for this metal is :
The number of photons per second on an average emitted by the source of monochromatic light of wavelength 600 nm, when it delivers the power of \(3.3\times10^{-3}\) watt will be : (h = \(6.6\times10^{-34}\) Js)
When the light of frequency \(2\nu_0\) (where \(\nu_0\) is threshold frequency), is incident on a metal plate, the maximum velocity of electrons emitted is \(v_1\). When the frequency of the incident radiation is increased to \(5\nu_0\), the maximum velocity of electrons emitted from the same plate is \(v_2\). The ratio of \(v_1\) to \(v_2\) is
The photoelectric threshold wavelength of silver is \(3250\times10^{-10}\) m. The velocity of the electron ejected from a silver surface by ultraviolet light of wavelength \(2536\times10^{-10}\) m is :
(Given h = \(4.14\times10^{-15}\) eVs and c = \(3\times10^{8}\) ms\(^{-1}\))
When a metallic surface is illuminated with radiation of wavelength \(\lambda\), the stopping potential is V. If the same surface is illuminated with radiation of wavelength \(2\lambda\), the stopping potential is \(\frac{V}{4}\). The threshold wavelength for the metallic surface is :
Photons with energy 5 eV are incident on a cathode \(C\) in a photoelectric cell. The maximum energy of emitted photoelectrons is 2 eV. When photons of energy 6 eV are incident on \(C\), no photoelectrons will reach the anode \(A\), if the stopping potential of \(A\) relative to \(C\) is
