All Flashcards
Describe the process of electron emission in the photoelectric effect.
- Light (photons) strikes a photoactive material. 2. If the photon's frequency is above the threshold frequency, an electron absorbs the photon's energy. 3. If the photon energy is greater than the work function, the electron is emitted with kinetic energy.
Define the photoelectric effect.
The emission of electrons from a material when light strikes it.
What is a photon?
A discrete packet of electromagnetic energy (light).
Define threshold frequency ().
The minimum frequency of light required to eject electrons from a material.
What is the work function ()?
The minimum energy needed to remove an electron from a material's surface.
Define maximum kinetic energy ().
The maximum kinetic energy of emitted electrons in the photoelectric effect.
What are the differences between light intensity and frequency in the photoelectric effect?
Intensity: Affects the number of emitted electrons. Frequency: Affects the kinetic energy of emitted electrons.
Compare the work functions of Sodium and Copper.
Sodium: Lower work function (easier electron emission). Copper: Higher work function (harder electron emission).
Differentiate between the particle and wave nature of light.
Particle: Light consists of photons with energy E=hf. Wave: Light has frequency, wavelength, and can diffract/interfere.
Compare electron emission above and below the threshold frequency
Above: Electrons are emitted, kinetic energy depends on frequency. Below: No electron emission, regardless of intensity.
Compare the effect of increasing light intensity vs. increasing light frequency on the photoelectric effect.
Increasing Intensity: More electrons emitted, but no change in their kinetic energy. Increasing Frequency: Electrons emitted with higher kinetic energy, provided frequency is above threshold.