All Flashcards
What is the effect of increasing the frequency of light above the threshold frequency in the photoelectric effect?
It increases the maximum kinetic energy () of the emitted electrons.
What is the effect of increasing the intensity of light on a metal surface above the threshold frequency?
It increases the number of emitted electrons, but not their kinetic energy.
What happens if the photon energy () is less than the work function (Φ)?
No electrons are emitted, regardless of the light's intensity.
What is the effect of using a metal with a higher work function in the photoelectric effect?
A higher threshold frequency () is required for electron emission.
What is the effect of shining light on a metal surface?
Electrons are emitted if the light's frequency is above the threshold frequency.
Contrast classical vs. quantum predictions regarding time delay in the photoelectric effect.
Classical: Noticeable delay. Quantum: Instant emission.
Contrast classical vs. quantum predictions regarding the effect of light intensity on kinetic energy.
Classical: Increasing intensity increases kinetic energy. Quantum: Increasing intensity does not increase kinetic energy.
Contrast classical vs. quantum predictions regarding the role of frequency in electron emission.
Classical: All frequencies cause emission if intensity is high enough. Quantum: There's a threshold frequency () below which no emission occurs.
Differentiate between the effect of light intensity on the number of emitted electrons vs. their kinetic energy.
Intensity affects the number of emitted electrons; it does not affect their kinetic energy.
What are the key differences between a photon and an electron?
Photon: Massless particle of light, energy = hf. Electron: Massive particle, orbits nucleus, can be ejected in photoelectric effect.
Define the photoelectric effect.
The emission of electrons from a metal surface when light shines on it.
What is a photon?
A discrete packet of light energy.
Define work function (Φ).
The minimum energy needed to remove an electron from a metal surface.
What is threshold frequency ()?
The minimum frequency of light required to eject electrons from a metal surface.
Define in the context of the photoelectric effect.
The maximum kinetic energy of an emitted electron.