"Why do heavy and light objects fall at the same speed?"
Using Captured Photons As Propulsion?
Purifying Water By Freezing
Gravity And Planets' Spin
Gravity And Light
Is The Universe Spinning?
Relative Motion And Electromagnetism
Beats Between Airplane Propellers
Harvesting Energy From Lightning?
Teacher Asks About Freezing Milk
Can We Calculate Radioactive Decays?
6666 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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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.