hover test

Veritasium takes an IQ test and examines what IQ measures, its history including military use and eugenics, its controversies, and how it correlates with life outcomes. Experts including Cecil Reynolds and Stuart Ritchie contribute.

3Blue1Brown explains why positive results on accurate medical tests are often false positives, and reframes Bayes' rule using likelihood ratios (Bayes factors) to update odds. It uses visual examples to make the reasoning intuitive.

Veritasium tells how Kodak film was fogged by radioactive fallout from the first atomic tests, letting the company detect nuclear testing before anyone announced it. The video also covers the deal to keep it quiet and how fallout contaminated packaging.

GoldenSound publishes music on Tidal to test MQA, a deep dive into the format's claims and problems including its leaky filter. Testing begins around the 5:45 mark.

Guitarist Jim Lill methodically tests what in an electric guitar affects its tone, swapping parts on a partscaster and even trying a 2x4 body. He finds that wood and construction matter far less than people assume.

Scott Manley explains the Cold War experiments in which steel and aluminium spheres, known as Lew Allen's Balls, were placed near nuclear detonations. The spheres survived the fireball, and he walks through what the declassified results show.

Scott Manley tells the story of a computerized telemetry system built to sit at the heart of a nuclear test device in place of the plutonium pit, designed to transmit data in the microseconds before it was destroyed.

A Medlife Crisis video by cardiologist Rohin Francis on overdiagnosis and over-screening. It explains how detecting more disease does not necessarily mean saving more lives, and covers harms such as unnecessary treatment.

Veritasium tells the story of the Fast Fourier Transform, from its use in detecting nuclear tests to Cold War politics, and how it could have changed the arms race. It includes a short, intuitive explanation of what the Fourier transform does.

Technology Connections explains why electric kettles are uncommon in the US, centering on 120V circuits limiting power. He tests ways of boiling water on gas, electric ranges and kettles.

Adam Savage and engineer Zach Radding examine Lumafield CT scans of Apple's $130 Thunderbolt 4 cable alongside cheaper USB-C cables. They explain the internal components that distinguish Thunderbolt from ordinary USB-C.

Adam Savage shows a set of Mitutoyo ceramic gauge blocks and uses them to explain metrology, the science of measurement. He argues that accuracy and precision work differently than most people assume, which changes how you think about every measuring tool.

Freya Holmer explains how Bezier curves work, from the helper-line construction to their uses in animation, text rendering and shapes. It uses visuals from her Unity Shapes plugin and was a SoME1 contest winner.

Veritasium explains why the one-way speed of light has never been measured, only the round-trip speed, since measuring it requires synchronized clocks that assume the answer. It explores the implications for relativity.

3Blue1Brown builds toy SIR models to simulate how an epidemic spreads and tests scenarios like social distancing, travel restrictions, central gathering places and quarantine. It was made during the early COVID-19 outbreak.

Matthias Wandel tests old and new code on a range of PCs, including a new mini PC, to measure how much faster modern hardware really is. He also shows optimization techniques such as branchless code, with benchmark programs on GitHub.

Veritasium explores how electrical energy actually travels in a circuit, arguing that it flows through electromagnetic fields around the wires rather than through the electrons. It builds a long-cable experiment with Caltech to test when a distant bulb lights.

Dave Plummer tours the IBM z16 mainframe from design through factory assembly, test lab, accelerators and water cooling. He explains why mainframes still exist and what makes them reliable.

Mark Rober digs into bed bugs, testing popular beliefs about where they come from and how to get rid of them. It mixes entertaining experiments with research-based advice on what works and what does not.

Aging Wheels tests how towing trailers affects the range of electric trucks, including a Silverado EV. It shows that trailer aerodynamics matters far more than added weight.

Geekerwan reviews smartphone CPUs by power efficiency rather than benchmark scores, with test methodology and chapters on Qualcomm, Apple, Samsung and Google chips. It explains why high benchmark scores can coexist with heat and poor battery life.

Scott Manley looks at SpinLaunch, which aims to throw launch vehicles out of a spinning launcher at hypersonic speed. He covers its recent Mach 1 test of a one-third scale launcher and the engineering problems that remain.

ACS Reactions investigates why Mexican Coke, supposedly cane sugar sweetened, tested as having glucose and fructose, explaining that sucrose breaks down in acidic soda.

Veritasium visits the US Navy's Crane facility to test top night vision goggles. It explains how image intensifier tubes and thermal or digital systems work and compares the generations of the technology.

Ben Eater explains why he builds computers on breadboards, including testing their signal behavior on an oscilloscope. It is a companion to his 6502 breadboard computer series.

Scott Manley surveys the research on whether people can adapt to rotating artificial gravity, from early Soviet centrifuge tests to modern studies. He concludes it is an engineering problem and discusses Coriolis effects and station radius.

Veritasium explains how investigators caught the Golden State Killer using forensic genealogy, matching crime scene DNA to distant relatives in public genealogy databases. It also covers the privacy implications of DNA databases.

The Thought Emporium follows up on his earlier video showing negative ion products are radioactive, reporting that Amazon pulled listings and companies shut down. He tests more radioactive quack products with a Geiger counter and cloud chamber.

James Hoffmann runs caffeine analyzer tests comparing filter versus espresso, extraction over time, steep time, instant coffee and light versus dark roast.

Autoline's John McElroy and Caresoft president Terry Woychowski look at the BYD Seagull, an electric hatchback that sells in China for about $11,500. Woychowski points out the cost-saving design and manufacturing choices, and McElroy takes it for a short test drive.

aGameScout explains rolling, the third major NES Tetris playstyle, in which players tap the back of the controller to move pieces faster than hypertapping. It covers how the technique works and where it comes from.

Geekerwan's Chinese-language review of Intel's Lunar Lake lightweight laptop chip, covering performance, perf-per-watt curves and battery life benchmarks. It tests whether x86 can compete on efficiency.

Oh The Urbanity! tests the theory that banning housing investors would fix affordability, using Rotterdam's ban as a case study. The video finds mixed results.

The Thought Emporium tests so-called negative ion and anti-5G wellness products and finds they are radioactive, with some coated in powdered thorium.

Tom Scott visits an eHighway test in Lubeck, Germany, where electric trucks with pantographs draw power from overhead wires. He explains how this could electrify road freight.

Technology Connections tests how quickly gas, induction and standard electric stoves boil water, with CO2 measurements and a discussion of the advantages and disadvantages of each.

Answer in Progress investigates why Japanese websites look different from those elsewhere, using an AI clustering approach to test the 2013 claim. It then looks at possible explanations.