A microwave oven is useful device that helps in cooking delicious food for us.
Have you wonder how it works?
A microwave oven works by using microwave radiation to heat food quickly and efficiently.
Microwave radiation
As the name implies, it uses microwaves radiation to heat food. Microwave radiation is a type of electromagnetic radiation that lies between radio waves and infrared waves in electromagnetic spectrum. It has a frequency range between 300 MHz and 300 GHz.
However in microwave oven, the frequency of microwave radiation is about 2.45 GHz.
How microwave oven works?
Microwave oven heat food using following steps:
- Inside the microwave oven, a component called a magnetron generates high-frequency microwave radiation (about 2.45 GHz).
- Microwaves heat food by interacting primarily with water molecules (but also fats and sugars to a lesser extent). When microwave radiation hit the water molecules, the energy is transferred to water molecules and as a result these molecules vibrate faster. Solid and liquid objects get heated when their molecules begin to vibrate faster. The more they vibrate, the more their temperature rise. High-Water-Content Foods (soups, vegetables) heat quickly because water absorbs microwaves efficiently. Fatty Foods heat more slowly because fats do not absorb microwaves as effectively as water.
- Microwaves do not penetrate deeply; usually only 1-2 cm into the food. This means that food is primarily heated near the surface, and heat is transferred inward by conduction.
- In order to ensure that food inside microwave oven heats uniformly, a turntable is placed inside the oven containment which rotates when the oven is turned on.
- Inside of the oven is made of metal. This is to make sure that microwaves get reflected off the metal surface and heat the food more efficiently.
Safety Aspect
Some of the safety related considerations relating to microwave oven are as follows:
- Microwave ovens are usually designed in such a way that if the door is opened then they immediately turned off thereby making them safe for everyday use.
- Another important safety aspect is never to use any metal plate inside oven to heat food. This is due to reason that if metal plate has sharp or thin edges, it can cause dangerous electrical arching which can potentially cause fire and damaging the oven.