The understanding that light interacts with matter like a particle also lead to modern information technology, like computers, TVs, and lasers. The communicator is a direct example of the Photo-Electric Effect, one of Einstein’s groundbreaking 1905 theses. This is the achievement for which he won the Noble Prize for Physics in 1921. The Photo-Electric Effect centers on the ability of light to free up electrons inside metal atoms. This induces electric current through out an illuminated piece of metal. The idea that light can physically disturb electrons denotes a particle nature of light. The energy produced is proportional to the frequency of light, not the intensity of light. This fact draws on the wave-like properties of light within the same interaction.
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Extension Activities
Laser Communicator – allow several students to communicate across the room. The laser emits high intensity light, which is absorbed by the photoreceptor on the receiver.