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- Einstein’s equation
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The momentum of a photon of de Broglie wavelength 5000Å is _______.
[Planck’s constant = 6.63 x10-34 J.s.]
(A) 1.326 x10-28 kg-m/s
(B) 7.54 x10-28 kg-m/s
(C) 1.326 x10-27 kg-m/s
(D) 7.54 x10-27 kg-m/s
Define (i) stopping potential and (ii) threshold frequency, using Einstein’s equation and drawing necessary plot between relevant quantities.
When radiations of wavelength λ1 and λ2 are incident on certain photosensitive, such that E1 > E2 . Then Planck's constant 'h' is ......................... .
(C = Velocity of light).
- `((E_1 - E_2)(lambda_1 - lambda_2))/(C(lambda_1 * lambda_2))`
- `((E_1 - E_2)lambda_1C)/((lambda_1 - lambda_2)lambda_2)`
- `((E_1 - E_2)lambda_1lambda_2)/(C(lambda_2 - lambda_1))`
- `((lambda_1 - lambda_2)C)/((E_1 - E_2)lambda_1 * lambda_2)`
Write Einstein's photoelectric equation and mention which important features in photoelectric effect can be explained with the help of this equation.
The maximum kinetic energy of the photoelectrons gets doubled when the wavelength of light incident on the surface changes from λ1 to λ2. Derive the expressions for the threshold wavelength λ0 and work function for the metal surface.
Find the value of energy of electron in eV in the third Bohr orbit of hydrogen atom.
(Rydberg's constant (R) = 1· 097 x 107m - 1,
Planck's constant (h) =6·63x10-34 J-s,
Velocity of light in air (c) = 3 x 108m/ s.)
Find the wave number of a photon having energy of 2.072 eV
Given : Charge on electron = 1.6 x 10-19 C,
Velocity of light in air = 3 x 108 m/s,
Planck’s constant = 6.63 x 10-34 J-s.
The photoelectric threshold wavelength of a metal is 230 nm. Determine the maximum kinetic energy in joule and in eV of the ejects electron for the metal surface when it is exposed to a radiation of wavelength 180 nm.
[Planck’s constant : h = 6.63 * 10-34 Js, Velocity of light : C = 3 * 108 m/s.]
The energy of photon of wavelength X is_____ .
[h = Planck’s constant, c = speed of light in vacuum]
The threshold wavelength of silver is 3800Å. Calculate the maximum kinetic energy in eV of photoelectrons emitted, when ultraviolet light of wavelength 2600Å falls on it.
(Planck’s constant, h =6.63 x 1O-34J.s.,
Velocity of light in air, c = 3 x 108 m / s)