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प्रश्न
Consider Figure for photoemission.
How would you reconcile with momentum conservation? Note light (photons) have momentum in a different direction than the emitted electrons.
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उत्तर
The momentum is transferred to the metal. At the microscopic level, atoms absorb the photon and its momentum is transferred mainly to the nucleus and electrons. The excited electron is emitted. Conservation of momentum needs to be accounted for the momentum transferred to the nucleus and electrons.
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संबंधित प्रश्न
The work function of the following metals is given : Na 2.75 ev, K = 2.3 eV, Mo = 4.17 eV and Ni = 5.15 eV. Which of these metals will not cause photoelectric emission for radiation of wavelength 3300 Å from a laser source placed 1 m away from these metals? What happens if the laser source is brought nearer and placed 50 cm away?
Answer the following question.
Define the term "Threshold frequency", in the context of photoelectric emission.
The wavelength λe of an electron and λp of a photon of same energy E are related by ______.
Emission of electrons by the absorption of heat energy is called ____________ emission.
Define the work function of a metal. Give its unit.
What do you mean by electron emission? Explain briefly various methods of electron emission.
Name the factors on which photoelectric emission from a surface depends.
Which unit is used for the work function?
What must supplied energy enable a metal electron to overcome for electron emission to occur?
Which particles at the surface hold free electrons inside the metal?
Under what condition does an electron escape after external energy is supplied?
Which are the three main ways electrons can be emitted from a metal surface?
When do electrons escape from a heated metal in thermionic emission?
What causes field emission?
What must fall on a metal surface for photoelectric emission to occur?
Which is an example associated with photoelectric emission?
