single answer

CGP Grey explains the Single Transferable Vote, a proportional ranked-ballot system, and why politicians have little incentive to adopt it. It is a short animated explainer of how multi-winner ranked voting works.

Technology Connections explains why single-hose portable air conditioners are inefficient and often a poor choice compared with window units. It details how the single hose pulls in warm outside air and wastes energy.

A PBS Space Time episode explaining why faster-than-light travel is equivalent to travelling back in time, using relativity and Minkowski diagrams for different observers.

A short BicycleDutch video on how the Netherlands got its cycling infrastructure, including the 1970s protests and the shift away from car-centric planning. The channel later published an updated version.

CGP Grey's quick, witty explainer on the differences between the United Kingdom, Great Britain and England, and the countries that make up the UK.

An animated 11-minute tour of the whole field of mathematics as a single map, showing how pure and applied math and their sub-fields relate to each other.

3Blue1Brown presents the Triangle of Power, an alternate notation that unifies powers, logarithms and roots in a single triangular symbol. The video shows how the inverse operations relate and how the notation could help.

An animated simulation comparing single-winner voting methods such as plurality, instant runoff and STAR. Colored regions show which candidate wins as a randomized electorate shifts across a two-dimensional political space, building on Ka-Ping Yee's earlier diagrams.

A 2011 remix of over six hours of talks by Kirk Sorensen and other thorium advocates, explaining thorium as a nuclear fuel and the liquid-fluoride thorium reactor (LFTR). It argues LFTRs could produce energy without long-lived transuranic waste.

America's Test Kitchen tests eight carbon-steel skillets to find the best one, asking whether a single pan can replace stainless, cast iron and nonstick. It names a winner and covers how the pans perform.

A mini-documentary by a Canadian living in Japan explaining how an average family can afford a new detached house in Tokyo. It covers how houses are treated as depreciating assets and how Japanese zoning and building practices keep prices low.

Practical Engineering compares modern concrete with that of the Roman Empire, covering modern techniques like roller compacted concrete and water-reducing admixtures. It explains the tradeoffs of Roman construction versus reinforced concrete.

An episode of Journey to the Microcosmos, hosted by Hank Green, about diatoms, single-celled algae with glass shells. It covers their role in producing a large share of Earth's oxygen and their uses in beer filtering, paint and kitty litter.

A Wendover Productions explainer on how budget airlines can sell tickets for under 10 euros. It covers the costs airlines face and how low-cost carriers structure their business.

Tom Scott explains why Britain historically has separate hot and cold taps rather than mixer taps, tracing it to how water was stored in tanks. He notes why the hot tap is not safe to drink from.

Veritasium visits Chernobyl, Fukushima and other places to find who on Earth is exposed to the most ionizing radiation. The answer turns out to be surprising and puts radiation risk in context.

A School of Life animated overview of Albert Camus, covering his existentialism and absurdism and his answer to the question of meaninglessness.

A short minutephysics video explaining why bicycles stay upright. It looks at gyroscopic precession, head angle and centre of mass, and shows that bikes self-steer toward the direction they lean.

A short explainer from Nat and Friends on where Google Earth's 3D imagery comes from, how it is stitched together, and how often it is updated. It describes aircraft carrying camera rigs and photogrammetry that turns the photos into 3D models.

Andreas Antonopoulos answers a question about how to secure your Bitcoin. He covers holding your own keys, backing up the 12 to 24 word seed phrase, and the tradeoffs of custodial accounts, phone wallets and hardware wallets.

Tom Scott explains why hold music sounds worse than it used to, tracing it to old telephone exchanges and the audio compression applied by modern switches. It is a short visit to the Milton Keynes Museum.

Numberphile talks with Grant Sanderson of 3Blue1Brown about a darts puzzle with a shrinking bullseye. Solving it takes the volumes of high-dimensional spheres, and the answer turns up Euler's number.

Matt Parker of Stand-up Maths explains single-pile Nim and the trick that wins it, using Dr NIM, a 1960s mechanical plastic computer that plays perfectly. He teaches the strategy so viewers can beat friends.

Andreas Antonopoulos answers a Bitcoin Q&A question about energy consumption in mining. He argues that mining is arbitrage for the cheapest electricity, drives investment in renewables, and that the traditional financial system has hidden externalities.