Stimulated Emission

Mr. Andersen explains stimulated emission in AP Physics Essentials video 137. He introduces the concept using red light and describes how photons can be directed coherently to form a laser. The video covers stimulated absorption and emission, using energy diagrams to illustrate photon interactions. It explains how lasers are built by reflecting photons with mirrors. A PHET simulation demonstrates these concepts, showing how wavelength affects energy levels and photon coherence. The video concludes by reinforcing the connection between energy levels and photon absorption or emission.

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