English

Define the Term 'Intensity of Radiation' in Terms of Photon Picture of Light.

Advertisements
Advertisements

Questions

Define the term 'intensity of radiation' in terms of photon picture of light.

Define intensity of radiation on the basis of photon picture of light.

Advertisements

Solution 1

The intensity of radiation is defined as the energy associated with photons emitted from a unit surface area in unit time

shaalaa.com

Solution 2

Intensity of radiation is defined as the number of photons falling per unit area in unit time. 

shaalaa.com
  Is there an error in this question or solution?
2014-2015 (March) All India Set 3

RELATED QUESTIONS

Light of intensity 10−5 W m−2 falls on a sodium photo-cell of surface area 2 cm2. 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?


What is the speed of a photon with respect to another photon if (a) the two photons are going in the same direction and (b) they are going in opposite directions?


Should the energy of a photon be called its kinetic energy or its internal energy?


A sphere of radius 1.00 cm is placed in the path of a parallel beam of light of large aperture. The intensity of the light is 0.5 W cm−2. If the sphere completely absorbs the radiation falling on it, find the force exerted by the light beam on the sphere.

(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


The work function of a metal is 2.5 × 10−19 J. (a) Find the threshold frequency for photoelectric emission. (b) If the metal is exposed to a light beam of frequency 6.0 × 1014 Hz, what will be the stopping potential?

(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


Find the maximum magnitude of the linear momentum of a photoelectron emitted when a wavelength of 400 nm falls on a metal with work function 2.5 eV.

(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


In an experiment on photoelectric effect, the stopping potential is measured for monochromatic light beams corresponding to different wavelengths. The data collected are as follows:-

Wavelength (nm):         350   400   450   500   550
Stopping potential (V): 1.45  1.00  0.66  0.38  0.16

Plot the stopping potential against inverse of wavelength (1/λ) on a graph paper and find (a) Planck's constant (b) the work function of the emitter and (c) the threshold wavelength.

(Use h = 6.63 × 10-34J-s = 4.14 × 10-15 eV-s, c = 3 × 108 m/s and me = 9.1 × 10-31kg)


In photoelectric effect, the photoelectric current started to flow. This means that the frequency of incident radiations is ______.


What changes the polarity between the plates?


What happens if the frequency of incident radiation is below the threshold frequency?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×