My teacher ask me this:
1. Which is simplest way to explain simplest to me?
2. What makes sky blue?
3. Why are clouds gray?
4. Why Star is sprikle?
5. How do you see the colors of the rainbow?
And I try to search the answer in the internet, it's difficult to answer this, even though you use internet, but I found the answer! it's take so much time.. here's the answer!
1. Which is simplest way to explain simplest to me?
Try to think back to when you were a little kid, or if you have younger cousin or sibling, think about how they are. Your little brother might ask questions all the time like, “Why is the sky blue?” A good answer for most people would be that the stuff that makes up air likes to move blue light around but not red light and so the sky is blue (rather than red). But a toddler would say, “Why?” And he would get another short answer. Then, he would say, “Yea, but why?” And on and on and on.
As it turns out, scientists are just like little kids that never grew up. Science is all about asking, “Why?”
We watch something happen and wonder why it happens. Then, just like a little kid would go ask a grown-up, we search for answers, often including our own educated guess. Sometimes the answers come to us just by thinking; sometimes they come when we notice patterns. When the ideas make sense and are supported by what we observe, we can tell everyone we know about it. And that is a simple way of explaining science: finding a problem, making a hypothesis, going through our procedure, collecting data, getting results, and forming a conclusion.
2. What makes sky blue?
White light from the sun passes through air fairly well, but there is a lot of air between here and the outer reaches of the atmosphere, and some of the light gets scattered. Scattering means that the light waves get their direction changed by the molecules and dust particles in the air. The thing is, all waves have something called wavelength, which is a measure of the distance between the crests of the waves. The wavelength of red light is the longest, and blue light has the shortest wavelength, with orange, yellow, green, blue and indigo in between. The key to this answer is that short wavelengths scatter better from small things than long wavelengths do. If we have lots of tiny things floating about in the water or air, like the tiny dots of fat and protein in the milk or tiny dust particles in the air, the blue-ish light gets scattered quite a lot, but the red-ish light gets scattered less. Take a breath, I know this is a long answer....
Lots of white light sets out from the sun and passes through the atmosphere. The deeper it gets, the more of the blue light gets scattered away from its original path. By the time it reaches the ground the white light has gone a bit yellowish, the color of what we call 'sunlight'. The blue light just bounces about, getting scattered like crazy, and all we see, instead of the starry diamond skies we see a big blue haze, which we call the sky.
There are a couple of other things you might like to know about this. When the sun gets really low in the sky, the light has to go through much more air, which is why the sun looks bright red (never look at the sun directly unless it's very low, near to sunset - you could go blind). Ever wondered why clouds are white? The droplets of water of which clouds are made are much bigger than the wavelength of red light, so it gets scattered just as much as the blue light does, so all of the white light scatters, not just the blue part.
Lots of white light sets out from the sun and passes through the atmosphere. The deeper it gets, the more of the blue light gets scattered away from its original path. By the time it reaches the ground the white light has gone a bit yellowish, the color of what we call 'sunlight'. The blue light just bounces about, getting scattered like crazy, and all we see, instead of the starry diamond skies we see a big blue haze, which we call the sky.
There are a couple of other things you might like to know about this. When the sun gets really low in the sky, the light has to go through much more air, which is why the sun looks bright red (never look at the sun directly unless it's very low, near to sunset - you could go blind). Ever wondered why clouds are white? The droplets of water of which clouds are made are much bigger than the wavelength of red light, so it gets scattered just as much as the blue light does, so all of the white light scatters, not just the blue part.
3. Why are clouds gray?
The color we see in clouds, the sky, or your clothes is determined by how light is transmitted (filtered) or reflected (bounced back like a mirror) by these objects.
Objects that are white, or any shade of grey, reflect or transmit equal portions of the color spectrum. You can see the colors of the spectrum, which range from red to yellow to green and blue, with a prism or in a rainbow. When an object absorbs some colors but reflects others, we see the color that is reflected. For instance, an orange absorbs blue light, but reflects red and yellow light so we see the color orange.
Clouds both reflect and transmit light from the sun, but they do not absorb any one of the colors we see much more than the others. So we see white when the clouds are thin and well lit, grey when they are thick, and almost black when they are very thick and block most of the sun's rays.
You are probably curious now as to why the sky is blue instead of white. That's because unlike clouds, the atmosphere scatters blue light more than the other colors of the spectrum. That scattered light from the sun is what we see when we look up at a clear blue sky.
Clouds are basically white because they scatter all wavelengths of light equally (in contrasts to the clear sky, which preferentially scatters blue wavelengths and lets the redder ones pass through).But, a thick cloud will be dark white, or gray, because it blocks a lot of the light! Does that make sense? I'm not sure I put that very well. Try this: When sunlight hits the top of a cloud it is scattered in all directions. Some gets scattered farther into the cloud. This light is scattered also, and a fraction of it is scattered farther into the cloud. The deeper into the cloud you go the less light is received from scattering above. In this way, the thicker the cloud, the less light gets through it. So, if you are looking at a whispy thin cloud it looks white. A thicker cloud looks gray, and a very thick thunderhead (cumulonimbus) will be almost black at the bottom because hardly any light gets through it.
4. Why star is sprinkle?
If you were looking from the Space Shuttle in orbit, you wouldn't see the stars twinkle at all. What makes the view different from here on earth is that the light from the stars must pass through our atmosphere, just as the sun's rays do.
The atmosphere can bend or distort light traveling through it when it is moving or heated. You can see this when looking down a long road on a hot day and the horizon shimmers, or when you look at something beyond a candle flame.
So it's not the stars that twinkle, really, but the air we look through that makes them appear that way
The atmosphere can bend or distort light traveling through it when it is moving or heated. You can see this when looking down a long road on a hot day and the horizon shimmers, or when you look at something beyond a candle flame.
So it's not the stars that twinkle, really, but the air we look through that makes them appear that way
5. How do you see the colors of the rainbow?
In order to see a rainbow we need rain, sunshine and an observer who has his/her back to the sun.
When white sunlight strikes a falling drop of water at a relatively low angle, the raindrop in the air acts like a prism. and the light is broken into a spectrum of red, yellow, green, blue, violet. When the light enters the raindrop, it bends (it refracts) differently depending on their wavelength. The violet light bends at a rather sharp angle, the red light is bent the least. The light continues into the drop and is reflected from the back of the drop to the front. When the beam hits the front it is refracted again and emerges from the drop as the color spectrum that we see in a rainbow.
Now, what we see as observers depends very much on where we are standing: Please look at the picture at the web site (which is also where I got my answer from):
http://science.howstuffworks.com/rainbow2.htm
It explains how we see the colors red and violet, the other rainbow colors are not shown to keep the picture simple.
When the light hits raindrop A only the red light is visible to the observer. We see the red light, because it is directed towards the observer's eyes. The violet light is directed above the level of the eyes and so are all the other colors, that is why we do not see them. However, in the lower drop (raindrop B) the red light is directed below the eye level and this time the violet light is visible to the observer. This means that we see only one color from each raindrop at a certain height. In the raindrop A we see only the red light, all other colors will exit at a lower angle and therefore be above the observers eyes. The sunlight will hit all the surrounding raindrops in the same way, so they will all bounce red light onto the observer and we will see a band of red. Raindrop B is much lower in the sky, so it doesn't bounce red light to the observer. At its height, the violet light exits at the correct angle to travel to the observer's eye. All the drops surrounding raindrop B bounce light in the same way. The raindrops in between A and B all bounce different colors of light to the observer, so the observer sees the full color spectrum.
This explains how we see the colors of the rainbow and you now also understand that the way we see the rainbow (faint or strong) depends on where we are standing.
Thank you for reading my article, I hope this helpful
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