Let There be Light Waves!!!!!!!!!!!!!!!!

Have you ever wondered how light waves work? No, I mean really. How do they travel? Well, here's some food for thought. It's imperative to our survival that light travels where there is nothing, not even air. Why? What's the biggest vacuum you can think of? The one in the closet? The one called your siblings room, where things enter and never leave? Wrong! Here's a hint: the largest vacuum is a big space! That's right, it's space! And guess what? If light didn't travel there, we'd all be dead! And if you don't believe me, think of how many things need light to survive and grow.



How does light move, you ask? Well, do you want the short or long answer? I'll give you the short. Light waves always move in straight lines. Have you ever been to Saskatchewan? I've been a couple times. If you have you'll have noticed that the place is so flat you can see the curvature of the earth. If you don't believe me then find out if you know anyone in Saskatchewan and get your parents to take you. Preferably driving. That way you'll see the highway, and that's one of the best places to veiw the curvature of the earth. Anyway, you can see things for miles because the light travels in a straight line.



Light always travels in a straight line. Imagine if it didn't! You wouldn't be able to see anything in front of you! That could get a little painful! :)

Filtering Light

Everyone likes colored lights. You put them on your tree at Christmas, unless you prefer white lights. Those exit signs in theaters and public places are orange. The lights on emergency vehicles are different colors, too. But the thing is, light is white, for the most part. So how do we get all these different colors?

To get different colors of light, we put our lights in colored tubes, or filters. Only certain colors can actually get through the glass, though, and that is why we have different colors. Some of the colors pass through, the rest are absorbed by the filter. The color we see, however, not only depends on the filter, but what the light is shining on.

If you put a red ball under a white light, you will see a red ball. If you put it under a red light, you will see a red ball. The red will probably be a slightly different shade, but it will still be red. Now, imagine if you put the same red ball under a green light. It will look like rather Christmasy, right? Wrong. The ball will be black. You see, the red ball absorbs the green light, so instead of looking like a really weird Christmas ornament, it rejects the black light, and that's what we see.

Here's one last interesting thing about light. The lights you have in your house produce more yellowish white light than the ones in stores. The lights in stores are usually fluoresent lights. This means that whatever is under the store lights looks a little different than in your house. This is a problem at paint stores, since not a lot of people realize that the sample they like looks different in their house!

Lights in the Sky

The main light in the sky is the sun. But it's not the only one. We have the northern lights, and rainbows. We'll talk about those two.

Everybody likes rainbows. They're so beautiful. If you ever want a rainbow and nature won't oblige, you can make your own. If the sun is behind you, and it's a sunny day, you can fill your mouth with water and spit on a window. (If this doesn't work, check The Encyclopedia of Immaturity and you'll find a more complete set of directions.) How do rainbows work, you ask? The sun's light shines through the individual water droplets, and the colors are different due to the way the light bends. Due to the angle from which we are looking at it, the rainbow appears to be an arch, but it's actually a circle.

And now, onto the northern lights, or aurora borealis. People who saw it before we knew what it really was thought it was angry gods, the swishing tails of foxes made from fire, the souls of dead warriors, or the reflection of a large school of herring (I am not making these up.) They can only be seen in winter. How do they occur? Charged particles from space, which come from the sun, enter the earth's atmosphere, attracted by our magnetic poles. (Some are attracted to the south pole: these form the southern lights.) They react with gas particles in our atmosphere to creat the breathtaking auroras.

Well, that's all for now. Adios!

Seeing Things

Eyes are just a ball of liquid. So why are they so important? I don't know, why are you asking me? Okay, that was a joke. I do know. I'm just trying to be funny. I'm also starting to sound like the big red button on www.randomwritersrambling.blogspot .com Well, anyway, back to the eyeball. Imagine being unable to see anything. Wow. There isn't much to see, is there? If you couldn't see, you would be fairly helpless. And do you know what lets you see (drumroll please) your eyes! (As if I needed to say that.) The front of your eye is called the cornea and is transparent. The cornea lets in light. The colored part is called the iris, and at the center is the pupil, which narrows or widens, depending on the amount of light you need to see. Inside your eye is a small lens. When light enters your eye, which is probably happening right now, little muscles move the lens so you can see better. The lens focuses a picture on the back, or retina. The picture, by the way, is upside down. The retina changes the picture into nerve signals, which are sent into the brain via the optical nerve. The brain turns the picture right side up and voila! you are seeing something. This is happening all the time. I advise you not to think about it too much though. It will give you a headache.

Well, that's all for now on the eye. Adios!

Relections

Mirrors are everywhere. You can walk past any number of them during the day. Some are windows, some are just relective surfaces, but a human's natural impulse is to look at their reflection whenever they walk by anything in which they can see themselves. Have you ever stopped to wonder how that works? Well, I am now going to explain it as clearly as I can.

Did you know that your skin color is not the color you think it is? You might think it's black or white or brown or whatever, but really, it's every color except the one you think it is! See, objects absorb color. I said that in an earlier post. (They also subtract color, but I'm not getting into that now because it would get too complicated.) Well, your skin absorbs every color except the one you think it is. In fact, it rejects the color, so that's what you see. When you look in a mirror, the rays of light bounce off because the surface doesn't absorb it.

Also, things that don't reflect can also be mirrors. Signs that show up when the carlights hit them are reflecting the light from your lights. Cats eyes reflect things as well. When the eyes of a cat or nocturnal animal are caught in the headlights of a car, the eyes glow back at us due to a reflective material in the backs of their eyes. Let's just hope that you brake before you hit the animal, eh?

That's all. Adios!

Electromagnetic Waves

Transverse waves are waves in which particles vibrate at right angles to the direction in which the wave is traveling. Electromagnetic waves are transverse waves made of constantly changing electric and magnetic fields. They are all invisible, except for the ones that make up light. They can also travel through almost anything. The range of waves, in order of frequency and wavelength, are on the electromagnetic spectrum. Frequency is the number of complete waves that travel past a point in one second. The wavelength is the distance between one wave and the low point of the next wave.

The rays toward the beginning are the gammarays. They are short and I think they are the ones used in chemotherapy. The next are the X-rays, the ones used to take X-rays. After that are the untraviolet rays, the ones which the ozone layer helps protect us from. After that are the visble light rays, the one we can see through a spectrum. After that are the infrared waves, given out by anything hot. Then we have the microwaves. We all know what those are used for. Last, we have rays that are used to broadcast radio and TV.

Well, I hope you've learned something about waves. Oh, here's a last little thing. All waves travel at the same speed, about 300,000 kilometers per second. Isn't that cool?