The concept of Threshold Frequency is central to understanding the Photoelectric Effect, a topic in Class 12 Physics that helped Einstein win the Nobel Prize.
Symbol: ν₀ (nu-naught).
Definition: Minimum frequency of light that causes photoelectric emission.
Formula: φ = hν₀.
Key Point: Intensity does NOT matter below threshold frequency — frequency is the deciding factor.
Threshold Frequency (ν₀) is defined as the minimum frequency of incident light required to eject electrons from the surface of a metal.
The threshold frequency is directly related to the Work Function (φ) of the metal — the minimum energy needed to release one electron from the metal surface.
Formula: φ = hν₀
Where:
Each metal has its own unique threshold frequency. Metals like Caesium and Potassium have low threshold frequencies (making them ideal for solar cells).
Threshold frequency (ν₀) is the minimum frequency of incident light required to eject an electron from a metal surface. Below this frequency, no photoelectric emission occurs regardless of the light's intensity.
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