Physics-
General
Easy
Question
Light of wavelength 2475 Å is incident on barium. Photoelectrons emitted describe a circle of radius 100 cm by a magnetic field of flux density 
Tesla. Work function of the barium is (Given 
- 1.8 eV
- 2.1 eV
- 4.5 eV
- 3.3 eV
The correct answer is: 4.5 eV
Radius of circular path described by a charged particle in a magnetic field is given by 
; where K = Kinetic energy of electron Þ 
By using E = W0 + Kmax
Þ 
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