Light of a certain energy shines on a metal and causes electrons to be emitted. Based on the research of Albert Einstein, what change would most likely result in stopping the emission of electrons from this metal?

In Einstein’s explanation of the photoelectric effect, each electron absorbs energy from a single photon, and photon energy is proportional to frequency. Lowering the light’s frequency can bring photon energy below the metal’s threshold energy, so electrons are no longer emitted. Changing intensity alone affects the number of photons, not the energy of each photon.

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