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Question of the Week

  • Why do microwaves hum?

    Dear T.J.,

    Long before humans invented microwave ovens, they had to rely on stoves or an open flame to heat up their food.

    These days, we can warm up food in a matter of minutes, or even seconds. A lot of parts had to be invented to make that all happen. These parts help electricity flow through the microwave in lots of different ways.

    One part called a transformer helps move the electricity from one area to another. As it does so, it may vibrate or shake a little, and that tiny movement can cause a humming noise.

    Electricity is actually a big part of … » More …

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