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प्रश्न
The electrons are emitted in the photoelectric effect from a metal surface.
पर्याय
only if the frequency of radiation is above a certain threshold value.
only if the temperature of the surface is high.
at the that is independent of the nature of metal.
with a maximum velocity proportional to the frequency of incident radiation
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उत्तर
The electrons are emitted in the photoelectric effect from a metal surface only if the frequency of radiation is above a certain threshold value.
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संबंधित प्रश्न
Photocurrent recorded in the microammeter in an experimental setup of the photoelectric effect vanishes when the retarding potential is more than 0.8 V if the wavelength of incident radiation is 4950 Å. If the source of incident radiation is changed, the stopping potential turns out to be 1.2 V. Find the work function of the cathode material and the wavelength of the second source.
The threshold wavelength of tungsten is 2.76 x 10-5 cm.
(a) Explain why no photoelectrons are emitted when the wavelength is more than 2.76 x 10-5 cm.
(b) What will be the maximum kinetic energy of electrons ejected in each of the following cases
(i) if ultraviolet radiation of wavelength λ = 1.80 × 10-5 cm and
(ii) radiation of frequency 4 x 1015 Hz is made incident on the tungsten surface?
Planck's constant is 6.6 × 10-34 Js. The momentum of each photon is given radiation Is 3.3 × 10-29 kg/s. The λ of radiation is ______.
The minimum frequency for photoelectric effect on metal is 7 × 1014 Hz, Find the work function of the metal.
Explain the concept of the photoelectric effect.
The energy of a photon is 2 eV. Find its frequency and wavelength.
The work function of a surface is 3.1 eV. A photon of frequency 1 × 1015 Hz. Is an incident on it. Calculate the incident wavelength is photoelectric emission occurs or not.
The maximum velocity of photoelectron emitted is 4.8 m/s. If the e/m ratio of the electron is 1.76 × 1011 C/kg, then stopping potential is given by ______
When a photon enters glass from air, which one of the following quantity does not change?
The maximum velocity of the photoelectron emitted by the metal surface is 'v '. Charge and mass of the photoelectron is denoted by 'e' and 'm' respectively. The stopping potential in volt is ______.
In photoelectric experiment, if both the intensity and frequency of the incident light are doubled, then the saturation of photoelectric current ______.
In photoelectric effect, for a light of different intensities but of same frequency, the stopping potential for a given metal is ____________.
A metal surface is illuminated by photons of energy 5 eV and 2.5 eV respectively. The ratio of their wavelengths is ____________.
When certain metal surface is illuminated with a light of wavelength A., the stopping potential is V, When the same surface is illuminated by light of wavelength 2λ, the stopping potential is `("V"/3)`. The threshold wavelength for the surface is ______.
In photoelectric effect, graph of saturation current versus frequency of light is plotted. The nature of the graph will be ____________.
Light of frequency 2 times the threshold frequency is incident on a photo sensitive material. If the frequency is made `1/3`rd and intensity is doubled then the photocurrent will ______.
Which one of the following statements ts INCORRECT for stopping potential in photoelectric emission?
The radiations of energies 1 eV and 2.5 eV are incident on a metal surface having work function 0.5 eV. The ratio of the maximum velocities of the emitted photo-electrons is ____________.
When a metal with work function 0.6 eV is illuminated with light of energy 2 eV, the stopping potential will be ____________.
Which one of the following graphs represents the variation of photoelectric current (i) with intensity (I) of the incident light?
The stopping potential in the context of photoelectric effect depends on the following property of incident electromagnetic radiation ______.
The radiation emitted, when an electron jumps from n = 3 to n = 2 orbit is a hydrogen atom, falls on a metal to produce photoelectron. The electrons from the metal surface with maximum kinetic energy are made to move perpendicular to a magnetic field of `1/320`T in a radius of 10-3m. Find the 320 work function of metal:
In a photocell, frequency of incident radiation is increased by keeping other factors constant (v > v0), the stopping potential ______.
Light of wavelength λ, which is less than threshold wavelength is incident on a photosensitive material. If incident wavelength is decreased so that emitted photoelectrons are moving with same velocity, then stopping potential will ______.
Light of two different frequencies whose photons have energies 1.3 eV and 2.8 eV respectively, successfully illuminate a metallic surface whose work function is 0.8 eV. The ratio of maximum speeds of emitted electrons will be ______.
Explain the failure of wave theory of light to account for the observations from experiments on photoelectric effect.
The threshold frequency for a certain metal for photoelectric effect is 1.7 x 1015 Hz. When a light of frequency 2.2 x 1015 Hz is incident on the metal surface, the kinetic energy of the emitted photoelectrons is 3.3 x.10-19 J. Calculate Planck's constant.
In a photoelectric experiment, the stopping potential is 1.5V. What is the maximum kinetic energy of a photoelectron?
