During Einstein’s Photoelectric Experiment, what changes are observed when the frequency of the incident radiation is increased?

The photoelectric effect is the emission of electrons from a material when it absorbs electromagnetic radiation. The electrons emitted in this way are called photoelectrons. In 1905, Albert Einstein proposed that the photoelectric effect could be explained by considering light as made up of discrete particles with energy proportional to their frequency. The photoelectric effect helps to illustrate the wave-particle duality of light.