spark

A man with no flight instruction and only desktop flight simulator experience attempts to take off and land a Cessna 172, with a commercial airline instructor aboard who gives no help. The flight came out of a prop bet.

Numberphile's Ben Sparks shows why the golden ratio is the most irrational number, using seeds, continued fractions and rational approximations. He also explains why plants use it for spacing leaves and seeds.

A short vintage film clip of Seymour Papert, creator of Logo, on using computers to spark children's imagination and learning.

Numberphile's Ben Sparks works through the physics of a car crash, showing how kinetic energy grows with the square of speed and why stopping distance climbs so quickly as velocity increases.