Threshold frequency: The observation that electrons are only emitted when the incident light exceeds a certain frequency, regardless of intensity, supports the idea of atoms absorbing photons of specific energies to release electrons.
Stopping potential: The linear relationship between stopping potential and frequency of incident light suggests that electrons gain a fixed amount of energy from absorbing individual photons with discrete energies.
Photoelectric current: The instantaneous emission of electrons upon light exposure and the immediate halt of current when light is turned off indicates the discrete nature of photon absorption by atoms, supporting the quantized energy transfer.
