Advertisements
Advertisements
प्रश्न
The wavelength λe of an electron and λp of a photon of same energy E are related by ______.
विकल्प
λp ∝ λe
`λ_p ∝ sqrt(lambda_e)`
`λ_p ∝ 1/sqrt(lambda_e)`
`λ_p ∝ lambda_e^2`
Advertisements
उत्तर
The wavelength λe of an electron and λp of a photon of same energy E are related by `bbunderline(lambda_p prop lambda_e^2)`.
संबंधित प्रश्न
Quarks inside protons and neutrons are thought to carry fractional charges [(+2/3)e; (–1/3)e]. Why do they not show up in Millikan’s oil-drop experiment?
Why should gases be insulators at ordinary pressures and start conducting at very low pressures?
How does one explain the emission of electrons from a photosensitive surface with the help of Einstein's photoelectric equation?
Would you prefer a material with a high work-function or a low work-function to be used as a cathode in a diode?
An isolated metal sphere is heated to a high temperature. Will it become positively charged due to thermionic emission?
A diode value is connected to a battery and a load resistance. The filament is heated, so that a constant current is obtained in the circuit. As the cathode continuously emits electrons, does it become more and more positively charged?
The cathode of a diode valve is replaced by another cathode of double the surface area. Keeping the voltage and temperature conditions the same, will the place current decrease, increase or remain the same?
The work function of aluminum is 4⋅2 eV. If two photons each of energy 2⋅5 eV are incident on its surface, will the emission of electrons take place? Justify your answer.
The wave associated with a moving particle of mass 3 × 10–6 g has the same wavelength as an electron moving with a velocity 6 × 106 ms–1. The velocity of the particle is
Emission of electrons by the absorption of heat energy is called ____________ emission.
What do you mean by electron emission? Explain briefly various methods of electron emission.
A 150 W lamp emits light of the mean wavelength of 5500 Å. If the efficiency is 12%, find out the number of photons emitted by the lamp in one second.
Photoelectric emission is observed from a metallic surface for frequencies ν1 and ν2 of the incident light (ν1 > ν2). If the maximum value of kinetic energy of the photoelectrons emitted in the two cases are in the ration 1 : n then the threshold frequency of the metallic surface is ______.
Give an example each of a metal from which photoelectric emission takes place when irradiated by
- UV light
- visible light.
Name the factors on which photoelectric emission from a surface depends.
The work function of a metal is 2.31 eV. Photoelectric emission occurs when the light of frequency 6.4 × 1014 Hz is incident on the metal surface. Calculate
- the energy of the incident radiation,
- the maximum kinetic energy of the emitted electron and
- the stopping potential of the surface.
