Hacking The Kendama With Physics
Summary
Michael Stevens and Hannah Fry explore the physics of the Japanese skill toy kendama, comparing a traditional wooden version with a custom Delrin model built by Adam Savage to demonstrate gyroscopic stability. They discuss how the heavier, machined plastic version uses center-of-mass alignment and spin to make catching the ball easier. The episode also covers viewer questions on the mathematical advantages of swimming hand positions, the internal structure of Jupiter’s "fuzzy core," and book recommendations for adults returning to mathematics and statistics.
Topics discussed
Introduction and the traditional Kendama gift
Sponsor: Cancer Research UK and space research
Sponsor: Alexa Plus and We Buy Any Car
Attempting to master the traditional Kendama
Physics of the Adam Savage custom Delrin Kendama
Machining process and material durability
Robotic learning and the cup-and-ball analogy
Kendama tricks and the joy of physical play
Gyroscopic stability and precession explained
Sponsor: Alexa Plus and We Buy Any Car
Q&A: The math and fluid dynamics of swimming
Q&A: The internal structure of Jupiter
Q&A: Recommended textbooks for adult learners
Hannah Fry's book recommendation: Hello World
Outro and call to action
Promo: The Rest is History on the French Revolution
Promo: Bear Hunt audio drama
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