"Can heat turn back into light?"
-Crews McCulloch (age 78)
So Hot You Can't See It?
Pushing On A Bar At One End
Moments In Time And Photographs
What Is The Vibrating Length Of A Guitar String?
Acceleration, Velocity, And Work
Why Do 'perpetual Motion' Toys Need Batteries?
Re-pressurizing Tennis Balls
Density Of Gas
6943 questions have been answered online since 1998 by volunteers from the Department of Physics at the University of Illinois' Physics Van outreach program. We've tried hard to make this the most reliable physics Q&A site on the Web, but no site is perfect, as we explain on this note. Our Baloney feature provides examples of how shaky many other sites are.
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