1. What is the Photoelectric Effect?

The photoelectric effect is the emission of electrons when electromagnetic radiation (like light) hits a material. The maximum kinetic energy of the emitted electrons is given by \( K_{max} = h f - \phi \), where \( h \) is Planck's constant, \( f \) is the frequency of the incident radiation, and \( \phi \) is the work function of the material.

2. How Does the Calculator Work?

The calculator uses the photoelectric effect equation:

Where:

• \( K_{max} \) — Maximum kinetic energy of emitted electrons (eV)
• \( h \) — Planck's constant (4.136 × 10^-15 eV·s)
• \( f \) — Frequency of incident radiation (Hz)
• \( \phi \) — Work function of the material (eV)

Explanation: The equation shows that the energy of the emitted electrons depends on the frequency of the incident light, not its intensity.

3. Importance of Photoelectric Effect

Details: The photoelectric effect was crucial in the development of quantum mechanics and has practical applications in solar panels, photodetectors, and image sensors.

4. Using the Calculator

Tips: Enter the frequency of the incident radiation in Hz and the work function of the material in eV. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What is the work function?
A: The work function is the minimum energy needed to remove an electron from the surface of a material.

Q2: What happens if hf < φ?
A: If the photon energy (hf) is less than the work function (φ), no electrons will be emitted regardless of light intensity.

Q3: Why is frequency important in the photoelectric effect?
A: The energy of photons is proportional to their frequency (E = hf), so higher frequency light can emit electrons with more kinetic energy.

Q4: What's the threshold frequency?
A: The threshold frequency is the minimum frequency \( f_0 = \phi / h \) needed to eject electrons from the material.

Q5: How does this relate to Einstein's Nobel Prize?
A: Einstein won the 1921 Nobel Prize in Physics for his explanation of the photoelectric effect, which helped establish quantum theory.