How can a microwave oven cook so fast?

Answer 1

The heat from a oven is slowly passed into the bread and the substance holds the heat upon removal relative to the time of heating. For a microwave, the substance is artificially raised in temperature from the outside in. As soon as the heat is stopped, the temporary warming stops and the core of the object is not as warm as the outer layers, pulling the heat inward. Cool replaces the heat as it goes inward. http://www.gallawa.com/microtech/howcook.html All liquids and food products, are made up of molecules. These molecules have positive and negative particles, so they tend to behave like microscopic magnets. As the positive half cycle of the microwave penetrates the food, the negative particles of the molecules are attracted and attempt to align themselves with this positive field of energy. Then, when the microwave energy alternates to the negative half cycle, the opposite occurs -- The negative particles are repelled and the positive particles are attracted, causing a flipping motion (actually, this reaction is the movement of the particles within each molecule, so, technically, they reverse polarity). This might be compared to a room full of people trying to run back and forth, from one side to the other. Obviously, there would be a lot of bumping, rubbing, agitation, and friction. Now, consider that the actual frequency of the RF energy used in microwave ovens is 2450 million cycles per second! Moreover, consider that within the course of one of those cycles, the molecules would actually change their direction (polarity) twice - once for the positive half-cycle and once for the negative half-cycle. This red-hot rate of vibration causes tremendous friction within the food, and - just as rubbing your hands together makes them warm - this friction produces heat. So the heat is produced directly in the food, but the food is not cooked, as is commonly believed, from the inside out. Actually, the cooking begins just beneath the outer surface and from there inward and outward, with the majority of the energy being expended in the outer layers. The rate and degree of heating depend on the depth and density of the food, as well as its ability to conduct heat. Because the microwave energy is changed to heat as soon as it is absorbed by the food, it cannot make the food radioactive or contaminated. When the microwave energy is turned off and the food is removed from the oven, there is no residual radiation remaining in the food. In this regard, a microwave oven is much like and electric light that stops glowing when it is turned off.

Answer 2

microwave is a genious tool. It uses the moisture/water in the food to heat it and therefore the energy comes from inside. While cooking in a pan, the energy is from outside.........therefore if you have any common sense you got the answer.

Answer 3

Microwaves are radio waves. In the case of microwave ovens, the commonly used radio wave frequency is roughly 2,500 megahertz (2.5 gigahertz). Radio waves in this frequency range have an interesting property: they are absorbed by water, fats and sugars. When they are absorbed they are converted directly into atomic motion -- heat. Microwaves in this frequency range have another interesting property: they are not absorbed by most plastics, glass or ceramics. Metal reflects microwaves, which is why metal pans do not work well in a microwave oven.

www.howstuffworks.com

Answer 4

because a frige makes ice. A microwave oven cook so fast because of its powerful electromagnetic Waves.

The reason microwaves cook food very quickly is because they able to penetrate into the food and cause the food to become heated. The food itself is surrounded by room temperature air which is invisible to the microwave, so all of the energy goes directly into the food and none is lost by heating the air. In conventional cooking, you have to first heat the air, which then heats the surface of the food, and the heat

transfers to the layer below it, and that then transfers the heat to the layer below that, etc., and so the heat slowly marches to the inside. Microwaves heat the outside and inside to be heated simultaneously microwaves, so it cooks quickly.

Answer 5

Conventional ovens use hot air to cook an item from the outside in. Microwaves use a completely different system. The magnetron, a vacuum tube comprised of several contrasting metals, produces microwave radiation that heats items from the inside out. The way it does this is pretty interesting: it actually excites water molecules within a piece of food. Water molecules are comprised of two oxygen atoms and one hydrogen atom, which are positively and negatively charged, respectively. The microwave radiation oscillates, causing the water molecule to rock back and forth in an attempt to line up with the shifting magnetic field. This movement creates heat.

For a better explanation, see the video "How a Microwave Oven Work" by engineerguyvideo on YouTube.

Answer 6

This depends on what speed you have the microwave oven and oven set on, what temperature, and how much power they both have.

Probably the oven would bake a cake faster, as it is bigger and has more power, and the ability to heat up faster.

Answer 7

Conventional ovens use hot air to cook an item from the outside in. Microwaves use a completely different system. The magnetron, a vacuum tube comprised of several contrasting metals, produces microwave radiation that heats items from the inside out. The way it does this is pretty interesting: it actually excites water molecules within a piece of food. Water molecules are comprised of two oxygen atoms and one hydrogen atom, which are positively and negatively charged, respectively. The microwave radiation oscillates, causing the water molecule to rock back and forth in an attempt to line up with the shifting magnetic field. This movement creates heat.

For a better explanation, see the video "How a Microwave Oven Work" by engineerguyvideo on YouTube.

Answer 8

i know