TL;DR If you want a quick way to gauge whether or not students understand the concept of potential energy, you can ask them to explain the origin of The World’s Most Annoying Negative Sign. It is merely a consequence of the very definition of potential energy, which is almost never explained coherently. In all of […]
Read More The World’s Most Annoying Negative SignThis question is particularly revealing in that it assesses whether or not students understand the coordinate-free nature of work as a dot product. Be prepared to hear such nonsense locutions as “negative force” or “negative displacement” but don’t be shocked when you hear them. I think it’s a product of the relatively poor treatment vectors […]
Read More Conceptual Understanding in Introductory Physics XXXVI: Geometry and WorkThis question might serve as a final exam for an introductory physics course. It could serve that purpose for my own courses, but it may not be appropriate for your courses so don’t worry if that’s the case. If you do not include system schemas in your course then this question won’t make any sense […]
Read More Conceptual Understanding in Introductory Physics XXVI: System SchemasAs usual, I’m posting this the Monday after the week named in the title. This week was all about chapter 6: energy and the energy principle. This is where Matter & Interactions really shines among introductory textbooks. I remember as a student being so confused by sign conventions that I honestly never knew when to […]
Read More Matter & Interactions I, Week 13