"Our class is studying the states of matter. My question is if glass can be a solid and a liquid can it be a gas?"
-Alex (age 9)
Temperature And Fields In Vacuums
Using Submerged Weight To Calculate Density
Can A Water Molecule Have A Temperature?
Light, Dark Matter, And Dark Energy
Practical Quantum Mechanics
Why Is There Gravity?
Geometry In Thin Film Interference Patterns.
Is Gravity Weak?
5987 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.
If you'd like to ask us a new question, not already covered, please read our answering guidelines first. We try to answer as many questions as we can, but it's not always possible to answer them all. Questions from kids are especially welcome.
Although we recommend not using our informal site as a cited reference, students who are in a rush and can't find a more proper peer-reviewed source can check our citation information section.