Recent content by hemmi

I'm currently reading Understanding Physics by Asimov and am stuck on an example he gives regarding conservation of momentum. What I don't understand is, why half the velocity? -2v makes sense to me if the momentum of the small mass "canceled out" an equal momentum of the larger mass, but...

Most physics textbooks when introducing the subject ignore the affect of air on moving objects for the sake of simplicity. I find it easier to first understand projectile motion in terms of pure theory, in a vacuum, as it describes will happen in %99.9999999 percent of the universe where there...

http://csep10.phys.utk.edu/astr161/lect/history/Newtongrav.html is a great resource, particularly the cannon picture. Good luck!

Well in fact, as ridiculous and beautiful as it sounds, the Earth pulls ever so slightly back on the sun and even your body pulls back on the earth. Given the huge mass differences however, it goes for the most part unnoticed. I may have misunderstood the last part of your question, but I...

Okay, let me first apologize for the belated response. I hope the future affords me more time to sit and ponder. Second, thank all of you for your quick, thoughtful, and welcoming replies. Regarding "mass contraction" I meant quite the contrary. I was talking about the increase in apparent...

Hey, I've been trying to get my head around Special Relativity and I'm having some trouble with the Lorentz Transformations. I have the impression that the contraction of time, length, and mass are equal, but the contrary impression that the length contraction is an effect of *measurement*...