I Heart Cardioids
Roll a circle around another circle of the same radius. A marked point on the first circle traces a curve called a cardioid. Mathematician Dave Richeson of Dickinson College, known as @divbyzero (opens new window) on Twitter, shares some fun explorations of this beautiful heart-shaped curve, which shows up in some of the most unexpected places.
Activities include printables to make your own cardioid curve and a flipbook animation, and of course, more about the math behind the curve!