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Physics

Power Efficiency

Quick fact

A typical incandescent light bulb has a power efficiency of about 2-3%, while an LED bulb can exceed 50% efficiency.

Why this is interesting

You flip a switch and a light bulb glows, but did you know that over 90% of the electricity it uses is wasted as heat, not light? Why do some devices convert almost all their power into useful work while others lose most of it?