Photoelectric Threshold Frequency
The minimum frequency of light required to eject electrons from a material. Below this frequency, no photoelectric effect occurs regardless of intensity.
Variables
Derivation
From photoelectric equation when kinetic energy equals zero.
Your notes
Constants in this formula
Check value
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- φ = 2 J (Work function)
- h = 6.626 070 15 × 10⁻³⁴ J·s (Planck constant)
Result: fthreshold = 3.01838 × 10³³ Hz
Other modern physics formulas with the same quantities
- Stopping Potential (Quantum Mechanics) shares Planck constant, Work function
- de Broglie Wavelength (Quantum Mechanics) shares Planck constant
- Particle in a Box Energy Levels (Quantum Mechanics) shares Planck constant
- Compton Scattering (Quantum Mechanics) shares Planck constant
- Photon Momentum (Quantum Mechanics) shares Planck constant
- Electron Wavelength (Accelerated) (Quantum Mechanics) shares Planck constant
Where this formula is listed
- Modern Physics formulas, under Quantum Mechanics, alongside Heisenberg Uncertainty Principle, Energy-Time Uncertainty, Time-Dependent Schrödinger Equation, Fermi Energy and Bragg's Law.
- In the modern physics list it comes after Fermi Energy and before Bragg's Law.
- Modern Physics formula sheet, one of 41 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Photoelectric Threshold Frequency formula?
Photoelectric Threshold Frequency is written f_threshold = φ/h. The minimum frequency of light required to eject electrons from a material. Below this frequency, no photoelectric effect occurs regardless of intensity. It belongs to Modern Physics, under Quantum Mechanics.
What are the units in f_threshold = φ/h?
In SI units, f_threshold is threshold frequency, measured in Hz; φ is work function, measured in J; h is planck constant, measured in J·s.
How is the Photoelectric Threshold Frequency formula derived?
From photoelectric equation when kinetic energy equals zero. The result is f_threshold = φ/h.