Friction at the atomic scale appears to depend on the speed at which two surfaces move past each other. This surprising behaviour was observed as the tip of an atomic force microscope (AFM) moves ...

Everybody loves a good, strong disagreement between two academics at the top of their game, especially when their positions are polar opposites. Two recent papers, by John Pendry of Imperial College, ...

Really, this is the experiment I wanted to start on. How does friction work in Bad Piggies? Let me start with a quick summary of my experiments so far. Scale. For the size of stuff in Bad Piggies, I ...

Speed is the rate at which something moves. Fast-moving objects have high speeds, slow-moving ones have low speeds, and objects with no movement have zero speed. Velocity, on the other hand, is speed ...

Avalanches, debris flows and landslides are key components of mass transport at the surface of the Earth. They have also been observed on other planetary bodies of our Solar System, from the interior ...