I learned to respect friction, as a phenomenon with many nuances, when I was a graduate student. One day, while teaching a problem session in elementary mechanics, I unwisely invented a new problem to ...

Sometimes you think you have a complete understanding of something and then BOOM—a simple problem throws everything out the window. Let's consider a very basic physics problem involving pushing a ...

Earlier, we saw that the work done by friction on a particle sliding on a rough surface is negative, causing a loss in total mechanical energy as the particle slides. Here, we will address the ...