How the Microwave Works

The science behind nuking that TV dinner
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Inside the Magnetron:

Large magnets impose a field that causes the outward-flowing cloud to revolve ( left ). As it does, it forms spokes that pass each cavity between the plates ( right ). A passing spoke provides negative charge to the cavity, which then falls off until the next spoke arrives.....[ More ]


High voltage is sent to the cathode filament. After it heats up, it emits electrons that the positively charged anode plates attract. The attached antenna resonates at 2.45 gigahertz and emits microwaves from its tip--just like a radio-transmission antenna.....[ More ]


Transformer, diode and capacitor raise household electricity from 120 to 3,000 volts or more and deliver it through a wire to a magnetron. The magnetron generates microwaves, sent by an antenna through a waveguide into the cooking chamber, where the waves reflect off metal walls.....[ More ]


Water molecules exist in most foods. They have positive and negative charge at opposite “ends.” The electric field of a microwave orients the positive ends in one direction, but the field reverses 4.9....[ More ]

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