Advertisements
Advertisements
प्रश्न
Choose the correct option.
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential ______.
विकल्प
Will depend on the average wavelength
Will depend on the longest wavelength
Will depend on the shortest wavelength
Does not depend on the wavelength
Advertisements
उत्तर
Polychromatic (containing many different frequencies) radiation is used in an experiment on the photoelectric effect. The stopping potential will depend on the shortest wavelength.
Explanation:
The photoelectric effect is the phenomenon of emission of the electron when the photon incident on the metallic surfaces.
• The electrons emitted from the metallic surface due to the photoelectric effect are called photoelectrons.
• The rate of emission of photoelectrons depends upon the frequency or wavelength of the incident light.
• When higher frequency or lower wavelength light incident on the metallic surface, more photoelectrons will be emitted giving rise to the photocurrent.
• Stopping potential is the minimum potential required for the prevention of ejection of photoelectrons due to the low wavelength radiations.
• In the case of polychromatic light, the radiation with high frequency and low wavelength will contribute to the ejection of electrons.
APPEARS IN
संबंधित प्रश्न
Is it always possible to see the photoelectric effect with a red light?
Explain the inverse linear dependence of stopping potential on the incident wavelength in a photoelectric effect experiment.
Define photoelectric effect.
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.
If the maximum kinetic energy of emitted electrons in photoelectric effect is 3.2 × 10-19 J and the work-function for metal is 6.63 × 10-19 J, then stopping potential and threshold wavelength respectively are
[Planck's constant, h = 6.63 × 1034 J-s]
[Velocity of light, c = 3 × 108 `"m"/"s"`]
[Charge on electron= 1.6 × 10-19 C]
Photoelectrons emitted from a metallic surface are initially ____________.
Threshold wavelength for lithium metal is 6250 Å. For photoemission, the wavelength of the incident light must be ______.
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?
A metal surface is illuminated by photons of energy 5 eV and 2.5 eV respectively. The ratio of their wavelengths is ____________.
The photo electric effect to take place for a metal, the minimum frequency required is 5.792 × 1014 Hz. A light of wavelength 6000 Å is incident on that metal surface. What is the corresponding frequency of light and will there be photoelectric emissions? [velocity of light = 3 × 108 m/s]
Light of different frequencies, whose photons have energies 3 eV and 18 eV respectively, successively illuminate a metal of work function 2 eV. The ratio of the maximum speeds of the emitted electrons will be ______.
Which one of the following statements ts INCORRECT for stopping potential in photoelectric emission?
A light of wavelength '`lambda`' and intensity 'I' falls on photosensitive material. If 'N' photoelectrons are emitted, each with kinetic energy E, then ____________.
Two incident radiations having energies two times and ten times of the work function of a metal surface, produce photoelectric effect. The ratio of maximum velocities of emitted photo electrons respectively is ____________.
An electromagnetic wave of wavelength '`lambda`' is incident on a photosensitive surface of negligible work function. If the photoelectrons emitted from this surface have the de-Broglie wavelength '`lambda_1`' then ____________.
When light of wavelength '`lambda`' is incident on photosensitive surface, photons of power 'P' are emitted. The number of photons (n) emitted in 't' second is (h = Planck's constant, c = velocity of light in vacuum) ____________.
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?
The wavelength of light incident on a metal surface is reduced from 300 nm to 200 nm (both are less than threshold wavelength). What is the change in the stopping potential for photoelectrons emitted from the surface will be ______ V. (Take h = 6.6 × 10-34 J-s)
The maximum kinetic energy of the photoelectrons ejected will be ______ eV when the light of wavelength 350 nm is incident on a cesium surface. The work function of cesium = 1.9 eV.
We wish to observe an object which is 2.5Å in size. The minimum energy photon that can be used ______.
For a given photosensitive material and frequency (> threshold frequency) of incident radiation, the photoelectric current varies with the intensity of incident light as:
Two radiations of photons energies 1 eV and 2.5 eV, successively illuminate a photosensitive metallic surface of work function 0.5 eV. The ratio of the maximum speeds of the emitted electrons is ______.
The photoelectric threshold for a certain metal surface is 3600 Å. If the metal surface is irradiated by a wavelength of 1100 Å, then kinetic energy of the emitted photoelectrons is ______.
If the maximum kinetic energy of emitted electrons in the photoelectric effect is 2eV, the stopping potential will be ______.
Light of wavelength 'λ' falls on a metal having work function \[\frac {hc}{λ_0}\]. Photoelectric effect will take place only if (λ0 is the threshold wavelength) ______.
A parallel plate capacitor with air between the plates has capacitance 9 pF. The separation between the plates becomes thrice and the space between them is filled with a medium of dielectric constant 6. The capacitance becomes 'x' pF. The value of 'x' is ______.
According to Einstein's photoelectric equation, the graph of kinetic energy of the photoelectron emitted from the metal versus the frequency of incident radiation gives a straight line graph whose slopе ______.
