Your Microwave Questions Answered

We answer your most frequently asked questions about microwaves.

Microwaves employ a device called a magnetron that uses electric current and magnets to generate electromagnetic waves ("microwaves"), which create a field with a positive and negative charge. These charges reverse direction an astounding 4.9 billion times per second.

Microwaves interact with water molecules and, to a lesser extent, oil. When water molecules, which have positive and negative charges, are exposed to the oscillating positive and negative charges of microwaves, they move at the same incredibly fast rate, bumping into one another (and into nearby molecules, such as fats and proteins) and increasing their temperature.

Microwaves strike the exterior of food and in most cases penetrate about an inch into the interior, causing water molecules to heat up. That heat energy then transfers to adjacent molecules, heating the rest of the food via conduction.

The holes allow users to see into the oven, and the metal reflects some microwaves back toward the food. The holes are small enough that microwaves can't fit through.

Microwaves bounce off the metal surfaces, back toward the center of the oven.

By rotating the food, the turntable helps microwaves reach—and heat—more of a food's surface.

When you lower the power level in a microwave, you decrease the amount of time the magnetron stays on. So, at 50 percent power, the microwave will emit electromagnetic waves for about 30 seconds out of a 1-minute cooking time by pulsing on and off intermittently. 

Microwave 2 cups water at full power until steaming but not boiling, about 2 minutes. Let sit for 5 minutes. Steam will loosen dried, stuck-on food. Wipe clean.