Physics Provides Answers to COMMON HOUSEHOLD QUESTIONS.

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Physics makes homes "live and breathe," but who thinks about science when looking at heat pumps, ceiling fans, or light bulbs? Few people realize that a little knowledge of physics can help homeowners conserve energy and save money on their utility bills.

Louis A. Bloomfield, professor of physics, University of Virginia, Charlottesville, and author of How Things Work: The Physics of Everyday Life, wants to change the commonly held view that physics is just a challenging course students take in high school or college. "One of the best-kept secrets is that physics is actually fun. Basic physics concepts are behind everything we do, and the way we heat, cool, and light our homes is a great example of the role that physics plays in our daily lives."

Whether you're looking for ways to conserve energy, reduce utility bills, or just learn a few basic concepts, physics can answer most common home energy concerns, including the following:

* The air from my heat pump isn't very hot. Is something wrong? Not at all. By warming the indoor air gradually with thermal energy gathered from outside your home, the heat pump is saving you money. Heat pumps are highly efficient because they use the laws of thermodynamics and a little commercial energy to transfer a tot of thermal energy from the colder outdoor air to the warmer air inside. Furnaces, on the other hand, are more wasteful because they convert a lot of commercial energy directly into thermal energy.

* Downstairs it's freezing; upstairs it's like a sauna. The basic physics here is that hot air rises and cool air falls. A well-located ceiling fan at the top of the stairs will not only blow heat back downstairs, it will warm the air as well. Moving hot air "excites" the atoms which add energy, raising its temperature.

* How can I stop my windows from letting in light and heat? Not only does visible sunlight pass easily through windows, but "invisible" light passes through, too, and that's where most of the heat is. Both kinds of light are part of the electromagnetic spectrum which ranges from longer-wave, lower-energy radio waves and microwaves to...