What is spaced repetition and does it work for physics?

Spaced repetition is a study technique where you review material at increasing intervals over time. Instead of cramming everything the night before a test, you review a topic after one day, then three days, then a week, then two weeks, and so on. Each successful review extends the interval.

The science behind it is solid. When you first learn something, you forget it quickly. But each time you successfully recall it, the memory becomes more durable and decays more slowly. Spaced repetition takes advantage of this by timing your reviews right before you'd forget, which is the most efficient point for strengthening the memory.

Does it work for physics?

Absolutely - but not all spaced repetition systems work well for physics.

General-purpose tools like Anki are designed for memorizing facts: vocabulary words, historical dates, anatomy terms. Physics is different. You're not memorizing isolated facts - you're building interconnected problem-solving skills. A flashcard that says "What is Newton's second law?" and answers "F = ma" doesn't prepare you to solve a two-body problem on an inclined plane. We go into this more in should I use Anki for physics.

What physics-specific spaced repetition needs

Feature	General tools (Anki)	PhysicsGraph
Problem variety	Same card every time	Different problems for the same concept each review
Implicit review	No - reviews each skill separately	Yes - solving a hard problem reviews all prerequisite skills
Scheduling	Manual deck management	Fully automatic
Card creation	You write them yourself	We generate them

How PhysicsGraph handles it

PhysicsGraph has a huge library of varied problems for each topic, tracks implicit review through the knowledge graph, and schedules everything automatically with our adaptive review system. You just log in, do your daily XP, and the system makes sure you retain what you've learned.