Advertisements
Advertisements
प्रश्न
Draw a plot showing the variation of photoelectric current with collector plate potential for two different frequencies, v1 > v2, of incident radiation having the same intensity. In which case will the stopping potential be higher? Justify your answer.
Advertisements
उत्तर
Effect of frequency of the incident radiation:
Taking radiations of different frequencies but of same intensity, the variation between photoelectric current and potential of plate A is obtained and shown in graph given below:
From the graph, we note:
(i) The value of stopping potential is different for radiation of different frequency.
(ii) The value of stopping potential is more negative for radiation of higher incident frequency.
(iii) The value of saturation current depends on the intensity of incident radiation, but is independent of the frequency of the incident radiation.
APPEARS IN
संबंधित प्रश्न
Draw a neat labelled circuit diagram of experimental arrangement for study of photoelectric effect.
Write three characteristic features in photoelectric effect that cannot be explained on the basis of wave theory of light, but can be explained only using Einstein's equation.
Sketch the graphs showing variation of stopping potential with frequency of incident radiations for two photosensitive materials A and B having threshold frequencies vA > vB.
(i) In which case is the stopping potential more and why?
(ii) Does the slope of the graph depend on the nature of the material used? Explain.
Two monochromatic beams, one red and the other blue, have the same intensity. In which case (i) the number of photons per unit area per second is larger, (ii) the maximum kinetic energy of the photoelectrons is more? Justify your answer.
In an experiment of the photoelectric effect, the graph of maximum kinetic energy EK of the emitted photoelectrons versus the frequency v of the incident light is a straight line AB shown in Figure 6 below:
Find:
1) Threshold frequency of the metal
2) The work function of the metal.
3) Stopping potential for the photoelectrons emitted by the light of frequency `v = 30 xx 10^14 Hz`
A photosensitive surface emits photoelectrons when red light falls on it. Will the surface emit photoelectrons when blue light is incident on it? Give reason.
Use Einstein's photoelectric equation to explain the observations from this graph ?
Calculate the momentum of a photon of energy 6 x I 0-19 J.
Light of wavelength 4000 Å is incident on two metals A and B. Which metal will emit photoelectrons, if their work functions are 3.8 e V and 1.6 e V respectively?
What must electrons near the metal surface overcome before they can escape?
