Question
Explain threshold frequency and stopping potential.###Define the following with respect to photoelectric effect :
(i) Work function (ii) Stopping potential
(i) Work function (ii) Stopping potential
✓
Answer
Threshold frequency : The minimum frequency below which photon is not capable of emitting an electron is called the threshold frequency. This is represented by $v_0$.
Stopping potential : The negative potential of plate C relative to P at which the photoelectric current becomes zero is called "stopping potential" or "cut off potential".
Work function : The minimum energy required for the emission of photoelectron from a metal is called the 'Work function' of that metal. Generally it represented by W or $\phi_0$. It is expressed in Joule and electron Volt.
Stopping potential : The negative potential of plate C relative to P at which the photoelectric current becomes zero is called "stopping potential" or "cut off potential".
Work function : The minimum energy required for the emission of photoelectron from a metal is called the 'Work function' of that metal. Generally it represented by W or $\phi_0$. It is expressed in Joule and electron Volt.
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