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 ...

Some forces are called contact forces because they require objects to touch. One is tension force, found in stretched wires. Another is the force found in a spring. And last are resistive forces: ...

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 ...

Forgive me for all the posts on ESPN's Sport Science (example: Pulling and Power). I can't help myself. In the short episode recently, Sport Science compared a football player pulling a sled with huge ...

I can't help myself. I have to say something about this awesome water slide as seen on io9. You really should check out the io9 article - an interesting read. But for me, let me see if I can estimate ...

Friction may well be nature’s most useful phenomenon. Without it, walking would be impossible and there would be no belt drives, no clutches, no wheels, and no brakes. However, in machinery in which ...

A famous demonstration of the counterintuitive power of friction involves two telephone directories with their pages alternately interleaved. People are then invited to pull the directories apart, a ...