How does a Microwave Oven work?

Question

Why is food heated, (and not just on the outside but all the way through) cutlery unaffected and metals exploded?

Answer 1

Your microwave operates at 2,450 Mhz (2.4 Gigahertz) radio frequency, but at a high power like 600-900 watts of radio transmission on a 900-1500 watt oven.

Since your oven is closed metal box, there are standing waves 3-4 inches from the beam and its paths, the standing waves have strong spots (crests) and weak spots (low amplitude troughs of the wave), that's why if you don't have a scattering device, you have a turn table so your food passes through these hot spots.

Answer 2

A microwave oven works using microwaves (hence the name).

The water molecules in the food absorb these microwaves, and start to vibrate due to a gain in energy. This movement is what causes the heating effect.

Because the microwaves can pass through the food, all the water molecules in the food absord energy, thus heating it all the way through.

There are dark spots in a microwave oven. Because microwaves are waves, there are parts where the wave energy is at a minimum. This means that any molecules there will not absorb energy. (To test this, put ants in a microwave and they will move to these cool spots; but I'm not saying you try this, as that would be cruel :P)

To solve this problem, the microwave oven rotates the food so all the water molecules gets exposed to the microwaves.

Answer 3

The microwaves are tuned to vibrational frequencies of water molecules so heat them up. But they do NOT penetrate all the way through the food. At best they penetrate an inch or so. So that is a bit of a myth.

Metals do no explode - they reflect microwave and - if in contact with one another - can gain induced currents leading to sparks. Most modern microwaves are not harmed by metals being present, though early ones were.

Answer 4

radiation from heat??