हिंदी

How Does One Explain the Emission of Electrons from a Photosensitive Surface with the Help of Einstein’S Photoelectric Equation? - Physics

Advertisements
Advertisements

प्रश्न

How does one explain the emission of electrons from a photosensitive surface with the help of Einstein’s photoelectric equation? 

संख्यात्मक

उत्तर १

Einstein’s Photoelectric equation is 

KEmax = hv - hv

eV0 = h(v - v0

From above equation
Case - I:

If v > v0  [Emission with K.E.]

If  v = v0 [Just emission]
If  v < v0 [No emission] 

shaalaa.com

उत्तर २

Einstein's photoelectric equation is, K. E = hv - Φ or hv = Φ + K. E.

This equation explains that when a photon of certain energy is incident on a photosensitive surface, a particular amount of energy gets used as a work function to eject electrons from their shells and the rest of the energy is acquired by ejected electrons as their Kinetic energy. The emission of electrons from a photosensitive surface takes place only if the incident energy of photons is greater than the work function.

shaalaa.com
Einstein’s Photoelectric Equation: Energy Quantum of Radiation
  क्या इस प्रश्न या उत्तर में कोई त्रुटि है?
2018-2019 (March) 55/3/3

संबंधित प्रश्न

In an experiment on the photoelectric effect, the slope of the cut-off voltage versus the frequency of incident light is found to be 4.12 × 10−15 Vs. Calculate the value of Planck’s constant.


Light of wavelength 488 nm is produced by an argon laser which is used in the photoelectric effect. When light from this spectral line is incident on the emitter, the stopping (cut-off) potential of photoelectrons is 0.38 V. Find the work function of the material from which the emitter is made.


Write Einstein’s photoelectric equation?


Define the terms (i) ‘cut-off voltage’ and (ii) ‘threshold frequency’ in relation to the phenomenon of photoelectric effect.

Using Einstein’s photoelectric equation shows how the cut-off voltage and threshold frequency for a given photosensitive material can be determined with the help of a suitable plot/graph.


The electric field at a point associated with a light wave is `E = (100  "Vm"^-1) sin [(3.0 xx 10^15 "s"^-1)t] sin [(6.0 xx 10^15 "s"^-1)t]`.If this light falls on a metal surface with a work function of 2.0 eV, what will be the maximum kinetic energy of the photoelectrons?

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


Use Einstein’s photoelectric equation to show how from this graph, 
(i) Threshold frequency, and (ii) Planck’s constant can be determined.


Each photon has the same speed but different ______.


There are materials which absorb photons of shorter wavelength and emit photons of longer wavelength. Can there be stable substances which absorb photons of larger wavelength and emit light of shorter wavelength.


A photon of wavelength 663 nm is incident on a metal surface. The work function of the metal is 1.50 eV. The maximum kinetic energy of the emitted photoelectrons is ______.


The photon emitted during the de-excitation from the first excited level to the ground state of a hydrogen atom is used to irradiate a photocathode in which the stopping potential is 5 V. Calculate the work function of the cathode used.


Share
Notifications

Englishहिंदीमराठी


      Forgot password?
Use app×