मराठी

Why it is the frequency and not the intensity of the light source that determines whether the emission of photoelectrons will occur or not? Explain. - Physics

Advertisements
Advertisements

प्रश्न

Why it is the frequency and not the intensity of the light source that determines whether the emission of photoelectrons will occur or not? Explain.

थोडक्यात उत्तर
Advertisements

उत्तर

The frequency, not the intensity, of the light source, determines the emission because if any incident light of a specific (i.e., threshold or more) frequency is incident, it results in emission regardless of its intensity.

shaalaa.com
  या प्रश्नात किंवा उत्तरात काही त्रुटी आहे का?
2021-2022 (March) Term 2 - Delhi Set 1

संबंधित प्रश्‍न

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


Can we find the mass of a photon by the definition p = mv?


Is it always true that for two sources of equal intensity, the number of photons emitted in a given time are equal?


Two photons of 


When stopping potential is applied in an experiment on photoelectric effect, no photoelectric is observed. This means that


When the intensity of a light source in increased,
(a) the number of photons emitted by the source in unit time increases
(b) the total energy of the photons emitted per unit time increases
(c) more energetic photons are emitted
(d) faster photons are emitted


An atom absorbs a photon of wavelength 500 nm and emits another photon of wavelength 700 nm. Find the net energy absorbed by the atom in the process.

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


When the sun is directly overhead, the surface of the earth receives 1.4 × 103 W m−2 of sunlight. Assume that the light is monochromatic with average wavelength 500 nm and that no light is absorbed in between the sun and the earth's surface. The distance between the sun and the earth is 1.5 × 1011 m. (a) Calculate the number of photons falling per second on each square metre of earth's surface directly below the sun. (b) How many photons are there in each cubic metre near the earth's surface at any instant? (c) How many photons does the sun emit per second?

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


On the basis of the graphs shown in the figure, answer the following questions :

(a) Which physical parameter is kept constant for the three curves?

(b) Which is the highest frequency among v1, v2, and v3?


Two monochromatic beams A and B of equal intensity I, hit a screen. The number of photons hitting the screen by beam A is twice that by beam B. Then what inference can you make about their frequencies?


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×