The stopping potential in the context of photoelectric effect depends on the following property of incident electromagnetic radiation :

Solution

Physics sir · 4 steps

Stopping potential measures the fastest electron's energy, and only the frequency of light sets that energy.

1. What it measures. The stopping potential V₀ is the reverse voltage that just stops the most energetic photoelectrons. So eV₀ equals their maximum kinetic energy.

   eV₀ = Kₘₐₓ = hν - φ

2. Read the equation. For a given metal the work function φ is fixed. The only property of the light in this equation is its frequency ν, so V₀ rises in a straight line as ν increases.
3. Intensity and amplitude. Brighter light, meaning larger amplitude or intensity, sends more photons per second. That ejects more electrons and raises the photocurrent, but each photon still carries hν, so V₀ does not change. Phase plays no part at all.
4. So. The stopping potential depends on the frequency of the incident radiation, option (b).

The idea to keep. In the photoelectric effect, frequency decides how much energy each electron gets, which fixes Kₘₐₓ and V₀. Intensity only decides how many electrons come out, which fixes the current.

Answer from the NTA final answer key. Solution by PrepWiser.