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Photoelectric Effect ⚡
Understand how light can eject electrons from a metal surface.
2026-03-21 · 2 questions
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2026-03-21
Question of the Day
Photoelectric Effect ⚡
Understand how light can eject electrons from a metal surface.
Question 1 of 2
What is the minimum frequency of light required to eject electrons from a metal surface called?
Discussion0
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Q1. What is the minimum frequency of light required to eject electrons from a metal surface called?
- Cut-off frequency
- Threshold frequency Correct
- Critical frequency
- Maximum frequency
Why
The threshold frequency is the minimum frequency of incident light required to release electrons from a metal surface. Below this frequency, no electrons are emitted regardless of intensity.
Q2. What happens to the maximum kinetic energy of emitted electrons if the intensity of incident light increases (frequency above threshold)?
- It increases
- It decreases
- It remains the same Correct
- It becomes zero
Why
The maximum kinetic energy depends only on the frequency of incident light, not its intensity. Increasing intensity increases the number of emitted electrons, not their energy.