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Physics

photovoltaiceffect

Quick fact

The photovoltaic effect was first observed in 1839 by French physicist Edmond Becquerel, who noticed that certain materials produced a small electric current when exposed to light—a discovery that took over a century to become practical.

Why this is interesting

You've seen solar panels on rooftops, silently generating electricity from sunlight. But how exactly does a solid piece of silicon turn light into usable electric power?