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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`
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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
The work function of caesium metal is 2.14 eV. When light of frequency 6 × 1014 Hz is incident on the metal surface, photoemission of electrons occurs. What is the
- maximum kinetic energy of the emitted electrons,
- Stopping potential, and
- maximum speed of the emitted photoelectrons?
How does one explain the emission of electrons from a photosensitive surface with the help of Einstein's photoelectric equation?
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 constant A in the Richardson−Dushman equation for tungsten is 60 × 104 A m−2K−2. The work function of tungsten is 4.5 eV. A tungsten cathode with a surface area 2.0 × 10−5 m2 is heated by a 24 W electric heater. In steady state, the heat radiated by the heater and the cathode equals the energy input by the heater and the temperature becomes constant. Assuming that the cathode radiates like a blackbody, calculate the saturation current due to thermions. Take Stefan's Constant = 6 × 10−8 W m−2 K−1. Assume that the thermions take only a small fraction of the heat supplied.
Answer the following question.
Define the term "Threshold frequency", in the context of photoelectric emission.
Why do metals have a large number of free electrons?
Define the work function of a metal. Give its unit.
In which case is electron emission from a metal not known?
Give an example each of a metal from which photoelectric emission takes place when irradiated by
- UV light
- visible light.
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.
