The Good Side of Radiation, Microwave Coffee
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What is the hottest thing ever in the entire universe? That hot stove or candle you touched when you were a kid is nothing compared to the heat of the sun. It’s a good thing we’re a good distance away from it. A few billions of kilometers that is. But the fact is that our sun isn’t the biggest, not by a long shot. Bigger stars produce more heat inside that core, thus making it hotter and brighter. So you can tell how big a star is by how bright it is. That of course, is very useful for scientists.
Unlike sound, heat doesn’t need to have a median. Sound needs particles and atoms in order to produce any sound, but heat doesn’t. There are 3 ways heat can move from one place to another. First, let’s discuss about radiation. Radiation is not all bad as it sounds like. We’d be better with radiation than without it.
How does your microwave work? It’s quite magical if you think about it. You put some frozen food inside the magic box, press some buttons and after some minutes it’s edible. Easy as pie isn’t it? Well, there’s something behind that magical box that makes it less magical.
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I’m sure you’ve heard of the word wave right? And your also might have heard of the word micro. Micro meaning small, while a wave is like… Uhh, it’s like a wave. You’ve been to the beach right? Those water waves keep on rocking back and forth. For a moment the ocean pulls the water in, then all of sudden gushes it back out. That’s a wave we can see, a water wave. But a microwave is way, way smaller than that.
And a microwave is just that. It heats up food by sending tiny waves from above. What was before rock solid can turn into slippery water. And the best part is the heat source and the food don’t even touch. On a hot afternoon, you decide to talk a walk outside. But then you forgot to wear your sandals. So what happens is the heat from the concrete floor transfers the heat to your feet. If heat is transferred by touching, then that is called conduction.
Have you ever noticed that when you stir a cup of hot coffee with a metal spoon, the heat from the tip of the spoon moves up? And this only goes more metal spoons. Wooden and plastic aren’t that effective. Why is that?
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We discussed just recently that radiation is without a median. Conduction is the opposite. Metal is a good conductor because their atoms are packed together, like a passenger train at rush hour. It’s dense, therefore the hot atom touches the next atom which touched the next atom. A chain of hotness that eventually spreads to the whole spoon!
But eventually your spoon and hot coffee will cool down. It can’t stay forever because around that hot cup of coffee is air. And if you are currently on earth, then you’re probably feeling that room temperature. The room temperature air will cool down your coffee because room temperature is cold compared to boiling hot coffee. So after some time it will cool down.
Thanks for Reading!
