Roper
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The microwave oven was invented in 1945, much farther back than most people realize. The first “Radarange” was sold in 1947. It cost $5000 and weighed 750 pounds. Since then, microwave ovens have come down in price and weight, but they operate on the same principles. Every microwave contains a part called a magnetron. The magnetron is a tube in which electromagnetic energy is emitted. The magnetron converts electricity to electromagnetic energy at a wavelength of 2.45 GHz. This wavelength of electromagnetic energy causes molecules to rotate by changing their polarity. As the molecules rotate, they heat up due to friction as they bump into each other during their rotation.
Open microwaves are dangerous to people and animals. Fortunately, microwave ovens come with several safety features that keep the microwaves from getting to us. First, microwaves cannot operate with the door open. A safety switch ensures the power stays off unless the door is closed. The construction of the microwave oven resists microwaves. So long as the door is closed and the walls of the microwave are intact, it is impossible for microwaves to escape.
Dangers of microwave ovens are in their improper use or in the effects of heating. Liquids in a container that give them a smooth surface can superheat in microwave ovens. Superheating is when the liquid reaches a temperature slightly above its boiling point. Any disturbance of the surface of the liquid will release the excess heat and it will boil suddenly, possibly causing it to jump out of the container.
Microwaving metal objects can also pose a risk. Most metal acts as an antenna in the oven. The microwaves focus on the metal and cause the walls of the microwave to melt or it can cause electric current to arc off the metal.
Other than these two factors, microwave ovens are perfectly safe.
 Posted 5384 day ago
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