Ask+Mr.+Mitchell



by Ayla

The School-Tacular Online Magazine has invited Mr. Mitchell to contribute to an ongoing feature called //Ask Mr. Mitchell//. In this feature, Mr. Mitchell will try to answer some of your burning science questions.

But first, let me tell you a little about Mr. Mitchell. Before he came to ASD in 2008, he taught science. His job at ASD is Science Coordinator for grades pre-K to 5. He works with teachers on putting together--you guessed it--science lessons. Mr. Mitchell is planning to make an outdoor science area with a pond for experiments. He told me that the most difficult questions kids ask him are about the universe and where humans came from.

And now it's time to ASK MR. MITCHELL!! **Question: Which is stronger—light or sound?** 
 * Mr. Mitchell's Answer**: Both light and sound are kinds of energy, so one isn’t really stronger than another- it depends what’s making the light or sound. For example, the light from the Sun is extremely strong- strong enough keep our Earth warm even though it’s about 150 million kilometers away! Sounds can be powerful too: in 1883 a volcano called Krakatoa had a huge eruption that was so loud it could be heard around the whole world! If you want to find out how strong a light or sound is, one clue is how much energy it uses, which is measured in Watts. For example, an ordinary light bulb uses 60 watts of energy to light up, and each of the speakers on my stereo system at home use 50 watts of energy. If your interested in learning more about strong lights and sounds- look up information on lasers and sasers.

**Question: Why isn’t there just one type of cloud?** **Mr. Mitchell's Answer**:  Clouds are made when water vapor (which is invisible tiny pieces of water) floating in the air start to join together and form bigger drops. This is called condensation. Once enough water vapor joins together the water droplets are big enough to see and you have a cloud. The kind of cloud you get depends on a few things: how much water is in the air, the temperature of the air, and how high in the air the water is. If there’s a lot of water vapor in the air, you can get very large and thick clouds- like cumulus or stratus clouds. As you go up higher in the sky, the air gets more spread out or thinner, so there’s less water vapor up there. This is why clouds very high in the sky, like cirrus, look so thin- they don’t have as much water in them. There’s a lot more to learn about clouds, for more information, check out NASA’s S’COOL project: asd-www.larc.nasa.gov/SCOOL/


 * Question: What makes the sky blue? **
 * Mr. Mitchell's Answer:** To understand this, you need to know that the light from the sun is made of a bunch of colors of light: red, orange, yellow, green, blue, and violet. If you ever experimented with a prism before you’ve probably seen this. When the light shines down from the Sun onto our Earth, it has to shine through a layer of air, called our atmosphere. Light shining through air can bump into the pieces of air and get scattered in different directions. Most of the different colors of light aren’t affected much by the air- they can shine straight through air. But blue light has just the right amount of energy that it bumps into the air and gets scattered a lot. When it scatters, some of that blue light shines down on us and this light make the sky look blue. If there weren’t any air to scatter the light the sky would be black, like out in space. So the next time you enjoy a beautiful blue sky- make sure to thank the air for it!