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Physic - Modern physic


The maximum kinetic energy of photoelectrons emitted from a surface when photons of energy 6 eV fall on it is 4 eV. The stopping potential in volts is :


Option

A. 2

B. 4

C. 6

D. 10



Correct answer is: B


EXPLANATION

Given, the maximum kinetic energy: 

Kmax = 4eV

If V0   be the stopping potential, then K max = eVo 

⇒ eVo = 4eV 

⇒Vo =4V

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