A certain metallic surface is illuminated with monochromatic light of wavelength λ. The stopping potential for photo-electric current for this light is 3V0. If the same surface is illuminated with light of wavelength 2λ, the stopping potential is V0. The threshold wavelength for this surface for photoelectric effect is [CBSE AIPMT 2015]
Find the de-Broglie wavelength of an electron with kinetic energy of 120 eV. [Karnataka CET 2015]
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If the momentum of an electron is changed by P, then the de Broglie wavelength associated with it changes by 0.5%. The initial momentum of electron will be [AIPMT MAIN EXAMINATION – 2012]
The work function of a substance is 4.0 eV. The longest wavelength of light that can cause photoelectron emission from this substance is approximately: [AIEEE 2004]
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 [MHT CET 2016]
Light of wavelength 500 nm is incident on a metal with work function 2.28 eV. The de Broglie wavelength of the emitted electron is [AIPMT 2015]
The de-Broglie wavelength ‘λ’ of a particle [MH CET 2015]
If the kinetic energy of a free electron doubles, its de Broglie wavelength changes by the factor [AIEEE 2005]
The surface of a metal is illuminated with the light of 400 nm. The kinetic energy of the ejected photoelectrons was found to be 1.68 eV. The work function of the metal is [AIEEE 2009]
Surface of certain metal is first illuminated with light of wavelength λ1=350nm and then, by light of wavelength λ2=540nm. It is found that the maximum speed of the photo electrons in the two cases differ by a factor of (2) The work function of the metal (in eV) is (Energy of photon=1240λ(in nm)eV)
If the de Broglie wavelength of an electron is equal to 10-3 times the wavelength of a photon of frequency 6×1014 then the speed (in m/s) of electron is equal to: (Speed of light =3×108 m/s) Planck's constant =
6.63×10-34 J.s Mass of electron =9.1×10-31 kg) is x × 104.what is x
In a photoelectric experiment, the wavelength of the light incident on a metal is changed from 300 nm to 400 nm. The decrease in the stopping potential (in V) is
(hc/e=1240 nm−V)
A particle A of mass 'm' and charge 'q' is accelerated by a potential difference of 50v another particle B of mass '4m' and charge 'q' is accelerated by a potential differnce of 2500V. The ratio of de - Broglie wavelength λA/λB is
In a photoelectric effect experiment the threshold wavelength of light is 380 nm. If the wavelength of incident light is 260 nm, the maximum kinetic energy (in eV) of emitted electrons will be: Given E(ineV)=1237/λ(innm)
A monochromatic source of light operating at 200W emits 4×1020 photons per second. Find the wavelength (in nm) of the light.