Campus Connection

Alum, science buff, answers perplexing questions about how the world works

Ever wonder why is snow white? Why you can’t see air? Or why do we have a change of seasons? If you’ve thought of a science question, alumnus Larry Scheckel, an author and science buff, has likely answered it. Scheckel, ’71 & ’78, a retired teacher, has been answering fundamental questions about how the world works since he started teaching science at Tomah High School 38 years ago. For more than 20 years, he’s contributed a weekly column “Ask Your Science Teacher” to the local Tomah Journal. In it he’s answered more than 750 questions from local kids. Below Scheckel shares responses to some of his favorite questions. Q: Why is snow white? A: To understand why snow is white, we must be familiar with what happens to light when it strikes any material. The color of anything, including snow, depends on how light interacts with it. Light is a rainbow of colors — the ROYGBIV colors, of red, orange, yellow, green, blue, indigo and violet. When photons of light strike an object, they may bounce off (reflect), bounce sideways (scatter), pass right through (transmission), or die by giving up their energy (absorbed). Grass is green because it reflects the green light to our eye and absorbs all the other colors. Red apples reflect red light to our eyes and absorb all the other wavelengths or colors. Snow is a bunch of ice crystals stuck together in a very complex arrangement. When light goes into snow, it hits all those ice crystals and air pockets, and bounces around and some comes back out. For white snow, all the colors come out. No one color or wavelength is absorbed or scattered more than any other. The “color” of all the light wavelengths combined equally is white. So all the colors coming out are the same colors that go in, namely, white light. Q: Why can’t you see air? A: Air is a gas. In gases, the molecules are so far apart that light does not reflect off of them like it does a solid. Instead, light passes through the molecules and doesn’t bounce back. That means we can’t see it. Q: Why do we have different seasons? A: Some people believe that we have warm summers because the sun is closer to us in the summer. But in fact, we on Earth are closest to the sun in the dead of winter, right around Jan. 4. And we Earthlings are farthest from the sun about July 5. To understand why Earth is warmer in summer and colder in winter, we must note that the Earth spins on its axis, much like a spinning toy top. As the Earth revolves around the sun, the axis of the Earth is always tilted at 23 and ½ degrees and always points to the same spot in the sky. Sometimes the sun is in the direction that the Earth is pointing, and sometimes it is not. The varying amount of sunlight the Earth receives during the year creates the seasons. We have hot summers in Wisconsin because the Earth leans toward the sun in June, July and August. We have cold winters because the Earth leans away from the sun in December, January and February. The Earth takes about 365 days, or one year, to go around the sun. As our Earth moves around the sun during the year, the amount of light each area of the Earth receives varies. In Wisconsin, we get about 15 hours of daylight in the middle of summer and only about nine hours of daylight in middle of the winter. It’s a double benefit. In the summer, we have more daylight hours and more direct rays of sun. The sun’s rays hit the Earth at a steeper angle because the sun is higher in the sky. The light does not spread out as much and the rays cover a smaller area. In the winter, we have fewer hours of daylight and the sun is much lower in the sky. The sun’s rays hit the Earth at a shallower angle and the rays are spread out over a bigger area. That means less sunlight for any given spot. Q: How risky is driving a car? A: Some risks, like driving a car, are easy to determine. Take the number of people killed in traffic accidents each year in the U.S. (about 36,000) and divide it by the number of people in the U.S. (about 300 million). So, your chance and my chance of being killed in a car accident each year is about 1 in 8,000. Other risks where numbers are not available are more difficult to calculate. Still people can reduce their risks of being killed or dying of unnatural causes by carefully monitoring lifestyle and behavior. People are aware of these behaviors, such as smoking, excessive drinking, overeating, not wearing seatbelts, etc. but some engage in them, nonetheless. We humans don’t always use common sense or gauge risk scientifically. When people are polled about risk, we won’t do anything in which the risk of dying is above 1 in a 1,000. Some people refuse to fly in airplanes, although air travel is, by far, the safest way to get from here to there. What’s a person to do? Don’t engage in known risky behaviors. Observe Aristotle’s Golden Mean for a successful and happy life. Moderation in everything and enjoy the good things of life!! Q: Do cats see in black and white?  A: It was once thought that cats were colorblind, but scientists now know better. Tests show that cats can tell the difference between certain colors. They basically see the world in shades of blue and green. They do not see the lower frequencies of red, orange and yellow. Research indicates that cats can distinguish more grades of gray than humans. They see less saturation in colors, so they don't see colors as vibrantly or intensely as we humans. Cats don't pay much attention to color. In their history and ancestry, color was not important to their survival. Motion was everything. Cats see even the slightest twitch. Their vision is blurred at the edges and they see best between 6 to 20 feet. About Larry Scheckel [caption id="attachment_6146" align="alignleft" width="253"] Larry Scheckel, ’71 & ’78, a retired teacher, has been answering fundamental questions about how the world works since he started teaching science at Tomah High School 38 years ago.[/caption] Scheckel earned an undergraduate degree in physics and math and a graduate degree in audio visual education media from UWL. He earned graduate degrees in science and science education from UW-Superior and UW-Madison, respectively. He taught physics and aerospace science to more than 4,000 high school students in Tomah during 38 years in the classroom. Named Tomah Teacher of the Year three times, Scheckel received the Presidential Award from the State of Wisconsin for six years. He received the Tandy Award, Kohl Award, Wisconsin Physics Teacher Award, Health Physics Society Award, Ron Gibbs Award, and Excellence in Science Teaching Award. Scheckel is the author of the science book, “Ask Your Science Teacher,” published in 2011 by CreateSpace. A second science book, “Ask A Science Teacher,” was published in 2013 by Experiment Publishing in New York. “Seneca Seasons: A Farm Boy Remembers” is a memoir of growing up on a Crawford County farm in the 1940s and 1950s and was published in 2014 by CreateSpace. Scheckel’s newest science book, “I’ve Always Wondered About That,” is scheduled to be published in Fall 2017 by TumbleHome Publishing in Boston. Learn more about Scheckel at https://larryscheckel.com/