The tiniest “ruler” ever is so precise that it can measure the width of a single atom within a protein. “We wanted to go from a microscope that maps positions of macromolecules relative to ...

NOTE: It takes some skill to fire the ruler consistently. Save for enthusiastic class. Description: A ruler is shot off a stool at different speeds using an elastic band. Objective: To learn about ...

It’s a fundamental principle of physics that particles with opposite ... But in a new study, scientists have discovered exceptions to the rule. When suspended in certain solutions, some charged ...