Concept:Stopping potential is a macroscopic experimental measurement used to determine the maximum kinetic energy of microscopic photoelectrons.
Formula:$$ eV_0 = K.E_{max} $$
Solution:- In the experiment, a reverse voltage is applied between the emitting and collecting plates.
- This retarding potential creates an electric field that slows down the ejected electrons.
- The specific voltage at which even the most energetic electrons are turned back—reducing the measurable current to precisely zero—is defined as the stopping potential.
Why other options are incorrect:While stopping potential is
proportional to the maximum kinetic energy (\( K.E_{max} = eV_0 \)), it is fundamentally an electric potential (measured in Volts), not an energy (measured in Joules or eV).
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