Ask the Physicist!

Do you have a question related to physics? If you do, you may submit your question, but please take a moment to read the brief policies below and the groundrules for the site before submitting your question. Note that there is an ask a question button on nearly every page you might visit. If my answer is to your liking, please consider making a donation to help support this service.

If you are here to find information about a particular topic in physics or just because you like to scroll science websites, you will find plenty of material to peruse here: since 1999 I have answered more than 7000 questions on-line and many more by brief email; all the questions answered on-line are accessibly archived. Because very large data sets like mine are often hard to navigate, I have curated the data by sorting the more interesting and useful questions/answers into categories, a link to which is at the top of every page. In addition you will find a search option, again linked to at the top of every page, which will search the entire raw data set.

For more than 35 years I taught physics at the college and university levels and I find that running AskThePhysicist.com has been a continuation of my love of education. I also was active in nuclear physics research performing experiments at particle accelerators around the world. I have earned AB, MA, and PhD degrees in physics at major universities. I try to provide clear, intuitive answers while retaining some degree of rigor when possible—real physics here. You can read more about my training and career, including a full Curriculum Vitae, on The Physicist page.

Policies: Questions which violate groundrules or which I consider to be "off the wall" will be discarded. Also, if your question is about astronomy, astrophysics, or cosmology, I may not answer because I have limited expertise. I recommend NASA's Ask an Astrophysicist. Another good place is Curious about Astronomy?