After decades of fighting with tangled wires, being able to drop your device onto a charging pad is a gamechanger.
Electrons are clever subatomic particles. Push them along a wire and you’ve got electricity. Coil that wire, and you get a magnetic field – that’s how electric motors get their push. Put the coil near another one with a shared iron core to direct the magnetism, and power is induced in the second coil – that’s how transformers change voltages.
Pulse electrons through the coil and you can separate the other coil a little further away, enabling you to put the emitter in a charging pad, and receiving antenna in a phone. Bring the phone within range and it will have electricity induced in its coil by the electromagnetic pulses resonating from the charging pad.
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Asked by: Gemma Lawrence
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