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प्रश्न
What is the photoelectric effect?
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उत्तर
The phenomenon of the emission of electrons from a metal surface when electromagnetic radiation of the appropriate frequency is incident on it is known as the photoelectric effect.
संबंधित प्रश्न
Can microwaves be used in the experiment on photoelectric effect?
Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.
Given the following data for incident wavelength and the stopping potential obtained from an experiment on the photoelectric effect, estimate the value of Planck's constant and the work function of the cathode material. What is the threshold frequency and corresponding wavelength? What is the most likely metal used for emitter?
| Incident wavelength (in Å) | 2536 | 3650 |
| Stopping potential (in V) |
1.95 | 0.5 |
The electrons are emitted in the photoelectric effect from a metal surface.
With the help of a circuit diagram describing an experiment to study the photoelectric effect.
State Einstein’s photoelectric equation. Explain all characteristics of the photoelectric effect, on the basis of Einstein’s photoelectric equation.
Which one of the following is TRUE in photoelectric emission?
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 ______.
The work function of a metallic surface is 5.01 eV. The photoelectrons are emitted when light of wavelength 2000 Å falls on it. The potential difference applied to stop the fastest photoelectrons is [h = 4.14 x 10-15 eV sec] ____________.
In photoelectric experiment, if both the intensity and frequency of the incident light are doubled, then the saturation of photoelectric current ______.
Light of wavelength `lambda` strikes a photo-sensitive surface and electrons are ejected with kinetic energy E. If the kinetic energy is to be increased to 2E, the wavelength must be changed to `lambda'` where ____________.
The threshold frequency for a certain photosensitive metal is v0. When it is illuminated by light of frequency v = 2v0, the maximum velocity of photoelectrons is v0. What will be the maximum velocity of the photoelectrons when the same metal is illuminated by light of frequency
v = 5v0?
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 ______.
When wavelength of incident radiation on the metal surface is reduced from 'λ1' to 'λ2', the kinetic energy of emitted photoelectrons is tripled. The work function of the metal is ______.
(h = Planck's constant, c =velocity of light)
Following graphs show the variation of stopping potential corresponding to the frequency of incident radiation (F) for a given metal. The correct variation is shown in graph (v0 = Threshold frequency).
The work function of a photosensitive material is 4.0 eV. The longest wavelength of light that can cause photon emission from the substance is (approximately) ____________.
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 ______.
Photoelectrons are observed to just emit out of a material surface when the light of 620 nm falls on it with the intensity of 100 W m-2. If the light of wavelength 400 nm is incident on the same material with an intensity of 1 W m-2, what would be the minimum reverse potential needed to stop the outflow of the electrons?
A charged dust particle of radius 5 × 10-7 m is located in a horizontal electric field having an intensity of 6.28 × 105 V/m. The surrounding medium is air with a coefficient of viscosity η = 1.6 × 10-5 N-s/m2. If the particle moves with a uniform horizontal speed of 0.02 m/s, the number of electrons on it is ______.
If the electron in hydrogen atom jumps from second Bohr orbit to ground state and difference between energies of the two states is radiated in the form of photons. If the work function of the material is 4.2 eV, then stopping potential is ______.
[Energy of electron in nth orbit = `-13.6/"n"^2` eV ]
On a photosensitive material when frequency of incident radiation is increased by 30%, kinetic energy of emitted photoelectrons increases from 0.4 eV. The work function of the surface is ______.
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 ______.
By increasing the voltage in an electron diffraction tube, the radius of the diffraction rings will ______.
Draw a neat labelled diagram of photo-current as a function of accelerating potential for fixed incident intensity but different incident frequencies for the same emitter material.
