Why do we use microwaves in microwave oven?

$ \begingroup $ Both visible faint and IR is used for cooking. visible light is used in solar ovens ( basically mirrors concentrating sunlight on a food token ). IR light is used in a normal oven ( the walls of the oven are heated, which causes them to radiate meaning total of hotness as IR ) ; grills use the same approach path, fair with higher temperatures. If you ‘ve ever baked/grilled something wrapped in tinfoil, the point of that is to exclude the IR radiation ( and trust on air heating alternatively ) .
So the first separate of the answer to your doubt is simple enough – if microwave ovens used visible or IR light, we would not call them microwave ovens, equitable ovens.

But microwave ovens were n’t sold as “ this is a bunch more amazing, because it uses microwaves ! ”. The sell steer of microwave ovens is that they heat the food with a lower baron stimulation. This requires two things ; first gear is conversion efficiency : how much electricity it takes to produce the radiation. however, a simple oven ( gas or electric ) is hard to beat in that deference – it ‘s very close up to 100 % efficient, since the waste heat is actually what causes the heat. Microwave ovens are built to use radiotherapy sources that are ampere effective as possible ( while besides not interfering with early electrical devices ), but those are still less efficient than a musical composition of resistive wire or an average light bulb.

sol if microwave ovens are n’t more efficient in power conversion, how come they ‘re so much faster at heating food ? Their deal point ( besides things like small size and weight ) was that they heat the food, not the container, and the oven, and the air, and …. This does n’t sound all that authoritative, but it ‘s actually a very big deal. Ovens need a lot of energy to heat up ; not a boastful deal if you ‘re cooking something for eight hours, or if you make a batch of meals ( e.g. pizza ovens in a restaurant ), but if you equitable want to heat a quick meal, most of the energy is wasted. Stoves need to heat the pan, and of course, even when you ‘re barely reheating a meal, you much need to heat quite a bit of excess urine ( and vaporize most of it, so the food is n’t inert ) .
Are microwaves uniquely suited for this task ? Kind of. They ‘re not promptly absorbed by kitchenware, and they ‘re not even scattered all that much ( compared to e.g. visible light reflecting off a egg white plate ). At the lapp prison term, they ‘re highly well absorbed by both water and fats, and most of our foods are entire of water. So you decidedly want very long beckon radiation. How farseeing ? That depends on other constraints. Too long waves mean the oven becomes excessively large, and one of the big benefits of microwave ovens is that they ‘re very small appliances. many frequency bands of long-wave radiation are already used for communication – radios, Wi-fi, cellphones … therefore you do n’t want to interfere with that. You besides need to avoid inducing stream in wires outside of the microwave. short waves are a lot more slippery to produce using the equipment – a radio receiver is more power efficient than a microwave, and visible light is even worse. An actual engineer who deals with microwave ovens could probably tell you a hundred constraints off the circus tent of his headway : )