Explore how forces and friction work to hold a block against a vertical wall. This video explains normal force, frictional force, and equilibrium conditions, showing how these forces balance 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 ...

Learn how to solve a ladder friction problem and determine the minimum coefficient of friction. Step-by-step explanations make it easy to understand the physics behind ladder stability and forces in ...

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 ...

Friction is an intrinsic physical phenomenon to curling. Without it, objects in motion would move endlessly, without slowing down. This would cause many safety-related problems: Cars or trains could ...

At a busy street crossing, people wait for the signal to change. When one person steps out first, others soon follow. Scientists in Amsterdam have found that this same kind of behavior happens at a ...

Here’s the rub with friction — scientists don’t really know how it works. Although humans have been harnessing its power since rubbing two sticks together to build the first fire, the physics of ...

Humans have been making fire using friction for thousands of years, with evidence of its use found in archaeological records across different cultures worldwide. Fire by friction is a testament to ...

In "Friction," tribologist Jennifer Vail shows how the fundamental force that resists motion keeps driving us forward.