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 ...

1.1 What is friction? Take this everyday example: when a coffee mug rests on a flat table, the kinetic frictional force is zero. There is no force trying to move the mug across the table, so there is ...

EVANSTON, Ill. -- Most people have experienced the hair-raising effect of rubbing a balloon on their head or the subtle spark caused by dragging socked feet across the carpet. Although these ...

Friction is a force that resists the motion of one object against another. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. Scientists began ...