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Physics

Wireless Power Transfer via Resonant Magnetic Coupling

Quick fact

Nikola Tesla demonstrated wireless power transmission over 100 years ago, but resonant systems remained largely a curiosity until the 21st century, when they were reinvented for practical charging devices.

Why this is interesting

You can charge your phone just by placing it on a pad—no wires, no plug. But how does electricity travel through the air, and why doesn’t it shock you?