THE VIRGINIAN-PILOT
Copyright (c) 1995, Landmark Communications, Inc.
DATE: Wednesday, March 1, 1995 TAG: 9503010039
SECTION: DAILY BREAK PAGE: E1 EDITION: FINAL
SOURCE: BY JAMES SCHULTZ, STAFF WRITER
LENGTH: Medium: 97 lines
YOUR MOM WAS right. Keep the refrigerator door closed. You'll be poorer - or at least hotter - if you don't.
``You can't cool the room by opening the refrigerator door,'' said Charles Hyde-Wright, an associate professor of physics at Old Dominion University. ``Yeah, there's lots of cold coming out of the refrigerator. But every refrigerator dumps heat back into the air, from the coils in the back.''
It's a vicious cycle, Hyde-Wright points out. As the room gets hotter, the fridge's compressor continues to run, trying to keep the food cold. The more the compressor runs, the hotter the room and the higher the electric bill.
Heat is on everybody's mind one wet, raw winter's day, as wind and rain lash at everything in sight. Hyde-Wright and Winston Roberts, an assistant physics professor at ODU, are dry for the moment, having come in from the cold to a spacious house in Norfolk to conduct a tour on household physics.
Physics? In the house? Shouldn't that be physics in the lab or in the think tank or down in the nuclear-tipped weapons pit?
Nope, say the physicist pair. Just look around you. From a home heating system, to the television, radio and the CD player, all of us are benefiting from at least one, and maybe two, centuries of basic physics research
It's been hard, long work to understand what happens at the smallest levels of creation, where atoms and their constituent parts - electrons, protons and neutrons - live.
Physicists have spent whole careers attempting to fathom small pieces of a very large puzzle. Their labors have directly led to the enormous variety of gadgets and conveniences that we take for granted.
Today, you can flip a switch and suddenly your hall or your bathroom is bathed in light. Turn up the thermostat and warm air wafts around you. Tired of jazz? Twist the radio dial and you can hear hip-hop, heavy metal or symphonies.
Time was, there wasn't anything on the airwaves. And you'd have to fire up a cord of wood or light candles, throw coal in the stove or turn on a gaslight if you wanted to stay comfortable and see what you were doing.
``Certainly, understanding how to manipulate hot and cold, and how to transform thermal energy into mechanical energy and back again was the great merger of physics and industry in the 18th and 19th centuries,'' Hyde-Wright said. ``This was the result of the original energy crisis, which was that people were running out of wood. It's still the only energy crisis that matters. Most people in the world are using wood to heat and cook.''
Producing and changing energy is the key to the relative prosperity and abundance of life in the late 20th century. Once we get energy, from fossil fuels, solar energy or nuclear power, we are able to channel it and transform it with integrated circuits, transistors and solid-state circuitry, the ODU scientists say.
Which brings us to the TV set. You don't think of it as an atom smasher, but physicist Winston Roberts says to think again.
``The CRT, or cathode ray tube, is essentially a very small accelerator, one of the smallest accelerators that exists today,'' he said. ``The principles that drive the cathode ray tube are exactly the same principles that drove the early accelerators. You have a large electric field, a reasonably evacuated region, and electrons traverse that space that's evacuated. That's essentially what an accelerator is.''
So the next time you're watching your favorite cop show or monster movie, tell yourself the pictures you're seeing are just electrons, lots and lots of electrons swirling around in a near vacuum and coating the inner surface of your screen. What could be better, watching a sort of electric paint flow across a glass tube inside a box you don't even have to get up to change?
Which brings us again to the kitchen and how energy is changed to make things warm and cold. There's the fridge, which cools by heating up a compressed gas; as the gas expands, it cools, keeping your goodies frosty. Then there's your oven, which cooks your goose by using electric coils to heat the air, which bakes your bird.
Don't forget the microwave, which owes its existence to radio and World War II-era radar installations. Contrary to conventional wisdom, a microwave oven is a kind of dedicated radio station that doesn't cook by heating from the inside out but from all directions at once.
The next time you microwave a burrito or a bowl of soup, think of a plucked violin string, Winston Roberts says. The kind of sound wave made by that string is similar to the waves bouncing back and forth in the microwave.
``That wave is tuned to water molecules in the food you're cooking,'' Roberts explained. ``Because you're exciting the motion of these molecules, you pump energy in, you get the molecules to move and this energy gets dissipated into random thermal energy into the entire body that you're heating. Essentially, you're cooking uniformly.''
Which maybe doesn't help you if you want your beef brown and your chicken crispy. But then, you're not hunkered down somewhere in the damp woods wearing animal skins trying to strike a spark so you and your tribe can scrape through another prehistoric night.
So be grateful for all those folks who write funny equations on the chalkboards and the laptops. Go put a cup of cocoa in the microwave. Raid the fridge. Crank up the heat, take a hot bath, turn on the tube, listen to some tunes.
If it's pouring or snowing outside, what do you care? You've got folks like Albert Einstein looking after you. ILLUSTRATION: Color drawing by Janet Shaughnessy, Staff
by CNB