Learn, Don’t Memorize!

Intro to Physics Blues As a high school student, I took physics my junior year and struggled to stay afloat in the class. While I was interested in understanding and applying the theories I learned, it was difficult to make sense of them in my head. As a result, I began my first collegiate physics course with a lot of excitement, yet some apprehension. I knew I would need to work extra hard to perform well in my classes so I made sure to get a head start. Before lectures, I read the relevant chapters, made thorough notes on the material, and memorized every concept. I partnered with my friends to review assignments and completed extra problems from my textbook. By the time I had to take my first test—I was ready to crush it! I felt confident and prepared, until I saw the questions †¦ Failure Frustration Panic swept over me when I realized that there were only variables on the page – no numbers. How could I possibly take a Physics test without calculating anything?!? As I tried to slowly work through each problem, I realized that while I spent a lot of time doing extra problems and getting the correct numerical answers, my understanding of the underlying concepts was shaky. When dealing entirely with concepts, instead of numbers, I was outside of my comfort zone and confused. Net force made theoretical sense to me, but during the exam I could not figure out how to orient my problem, especially when presented with multiple masses in different configurations. Memorizing Newton’s law, F = ma, was not useful when I did not understand how force vectors summed to a net force. I submitted my exam, uncomfortable with the concepts and frustrated with myself for how unprepared I was with the application. Not only was I motivated to do better on my next exam, but also to learn better. Learn Better The next unit we covered was on center of mass and linear momentum. This time, instead of memorizing a bunch of equations and definitions, I engaged with the concepts I learned in class. Engaging with the concepts made me question whether a definition or equation actually made sense to me by constantly trying to mathematically prove it. One of the topics I had trouble with in this unit was collisions. I â€Å"knew†, by definition that during elastic collisions the kinetic energy of the colliding body may change, while the total kinetic energy of the system did not but, I did not understand why it was important that there was a conservation of kinetic energy for elastic collisions. In order to resolve this gap in reasoning, I had to revisit the chapter on energy and relate the concepts to linear momentum. When solving problems, I also drew my system and the velocity vectors relating to every mass to visualize how masses moved relative to each other after a collision. For me, being able to visualize theoretical concepts was a breakthrough and solidified my understanding of how energy, velocity and momentum were related even more. As I enrolled in more physics classes throughout the subsequent years, I ditched my flashcards and stopped trying to memorize every single definition I came across. Instead I tried to define the words in terms that made sense to me and asked my Teaching Assistants to either validate or correct my definitions. I spent more time on problems, focused on understanding latent concepts, equations, and their visualizations, instead of plugging and chugging an equation absentmindedly. I worked out the mathematical derivations and equation proofs, which was helpful in forcing me to think about how the concepts made mathematical sense. The key to my understanding in physics was not to memorize formulas, but to ask myself â€Å"Does this make sense? Why?† And in asking myself these questions, I learned physics better than I ever had before. Yilma is a native New Yorker and a recent graduate of Columbia University where she completed her bachelor’s degree in Physics. Yilma began tutoring while she was a sophomore in high school. Her approach to tutoring is systematic, thorough, but more importantly, fun! ; Interested in learning more about physics? Check out some other awesome blog posts below! Why logarithms are actually useful: Simplifying Arrhenius temperature dependence using log tricks Astronomy vs. Physics: Cultural Differences Inertia Experiments Rolling Motion Part I