Is pitch a liquid or a solid? It turns out that while it appears to be a solid at room temperature, it actually flows like a liquid ... a very, very viscous liquid. Why is this interesting? One of the ...

If you’ve ever whacked the bottom of a ketchup bottle to get that tasty tomato goop flowing, you’ve put some serious physics to work. Ketchup is a non-Newtonian fluid. So are toothpaste, yogurt, ...