Photoelectric Effect

Step 1: Understand the photoelectric effect.
The photoelectric effect occurs when light of a sufficiently high frequency strikes a metal surface and ejects electrons.
The frequency of the light must be above a certain threshold frequency to overcome the work function of the metal.
Step 2: Identify the most effective radiation.
Ultraviolet radiation has higher energy than visible light, and its frequency is above the threshold for most metals, making it the most effective for the emission of electrons.

Step 1: Photoelectric effect.
According to Einstein's photoelectric equation, the kinetic energy of emitted electrons depends on the frequency of the incident light: where is Planck's constant, is the frequency of the incident light, and is the work function of the metal.
Step 2: Identify the correct option.
The kinetic energy of the emitted electrons increases with the frequency of light, and not with the light intensity.