Will This Go Faster Than Light?

January 23rd, 2014

Physics of contraptions meant to go faster than light.
Audible: http://bit.ly/AudibleVe
My video about the problem with Facebook: http://bit.ly/PwFB

Special thanks to MinutePhysics for visual effects and Prof. Geraint Lewis for revisions to earlier drafts of this video.


We Tagged a Great White Shark!

December 21st, 2013

Veritasium second channel: http://bit.ly/2Veritasium
Rodney Fox Shark Attack Story: http://bit.ly/1frAwlI
Check out Audible: http://bit.ly/AudibleVe

For this video I went off the coast of South Australia to an island frequented by great white sharks. Here they hunt seals and fish. I’ve never been scuba diving before but I got into a cage and filmed the sharks under water. It was an incredible experience. Then we came back on the surface to tag the sharks.


How We’re Fooled By Statistics

November 23rd, 2013

Is punishment or reward more effective as feedback? Do new medical treatments really work? What about streaks in sport? Without considering regression to the mean, we are prone to making significant errors.

Check out Audible.com: http://bit.ly/ZJ5Q6z
Filmed at Perimeter Institute: http://pitp.ca

Is punishment or reward more effective for helping people learn. A lot of people would say different incentives motivate different people, or in different circumstances, but in psychology there is a sizable body of evidence that in order to learn skills, positive feedback is more effective. This fining has been verified not just with humans, but also with other species.

It was strange then that after Daniel Kahneman discussed this research with Israeli fighter pilot instructors that he was met with resistance. They found the opposite was true: when they reprimanded a cadet for performing poorly, he invariably improved, but if they praised a cadet for an excellent performance, the next attempt was not as good. In order to solve this apparent contradiction we first need to understand regression to the mean.

Teacher study: http://bit.ly/1h8puVT
Rugby player study: http://bit.ly/1aNSrBI


How Special Relativity Makes Magnets Work

September 23rd, 2013

MinutePhysics on permanent magnets: http://www.youtube.com/watch?v=hFAOXdXZ5TM
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Magnetism seems like a pretty magical phenomenon. Rocks that attract or repel each other at a distance – that’s really cool – and electric current in a wire interacts in the same way. What’s even more amazing is how it works. We normally think of special relativity as having little bearing on our lives because everything happens at such low speeds that relativistic effects are negligible. But when you consider the large number of charges in a wire and the strength of the electric interaction, you can see that electromagnets function thanks to the special relativistic effect of length contraction. In a frame of reference moving with the charges, there is an electric field that creates a force on the charges. But in the lab frame, there is no electric field so it must be a magnetic field creating the force. Hence we see that a magnetic field is what an electric field becomes when an electrically charged object starts moving.

I was inspired to make this video by Prof. Eric Mazur http://mazur.harvard.edu/emdetails.php

Huge thank you to Ralph at the School of Physics, University of Sydney for helping us out with all this magnetic gear. Thanks also to geology for loaning the rocks.

This video was filmed in the studio at the University of New South Wales – thanks to all the staff there for their time and support.

Music: Firefly in a Fairytale, Nathaniel Schroeder, and Love Lost (Instrumental) by Temper Trap licensed from CueSongs.com


The Bullet Block Experiment

August 20th, 2013

Higher: http://bit.ly/blockhigher
Same height: http://bit.ly/SameHeight
Lower: http://bit.ly/BlockLower

Special Thanks to:
Henry (MinutePhysics): http://www.youtube.com/minutephysics
Destin (Smarter Every Day): http://www.youtube.com/smartereveryday
Greg and Mitch (ASAP Science): http://youtube.com/asapscience
Elise Andrew (I F***ing Love Science): http://youtube.com/iflscience

Thanks to everyone at RIT and Dickinson College who helped with the making of this video:
Rochester Institute of Technology
Robert Teese, Katelyn Wilkerson, Andrew Gillie, Andrew Stidwill

Dickinson College
This experiment was the brainchild of David Jackson based on a demo at Princeton.
Priscilla Laws, Catrina Hamilton-Drager, Maxine Willis

High-speed camera support:
Charles Zwemer and Bria Antoine


How Does a Transistor Work?

July 9th, 2013

How does a transistor work? Our lives depend on this device.
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When I mentioned to people that I was doing a video on transistors, they would say “as in a transistor radio?” Yes! That’s exactly what I mean, but it goes so much deeper than that. After the transistor was invented in 1947 one of the first available consumer technologies it was applied to was radios, so they could be made portable and higher quality. Hence the line in ‘Brown-eyed Girl’ – “going down to the old mine with a transistor radio.”

But more important to our lives today, the transistor made possible the microcomputer revolution, and hence the Internet, and also TVs, mobile phones, fancy washing machines, dishwashers, calculators, satellites, projectors etc. etc. A transistor is based on semiconductor material, usually silicon, which is ‘doped’ with impurities to carefully change its electrical properties. These n and p-type semiconductors are then put together in different configurations to achieve a desired electrical result. And in the case of the transistor, this is to make a tiny electrical switch. These switches are then connected together to perform computations, store information, and basically make everything electrical work intelligently.

Special thanks to PhD Comics for awesome animations: http://bit.ly/16ZXcVY

And thanks to Henry Reich and Vanessa Hill for reviews of earlier drafts of this video.

Music: Kevin MacLeod (incompetech.com) Decisions


Can We Really Touch Anything?

June 24th, 2013

Can we really touch things? Well if by touch we mean exchange a force-carrying particle with, then yes. The photon is the force-carrier of the electromagnetic interaction. But if the photon is also a particle of light then why aren’t magnets glowing? Because the photons are virtual particles, which means they can’t be directly detected (without changing the outcome we are trying to measure.
Supported by Audible: http://bit.ly/ZJ5Q6z
Who would win in a chin-up competition between me and MinutePhysics? What is going to be the most exciting area of scientific discovery in the next few decades? Where can you get a Veritasium t-shirt? http://dft.ba/-vetshirt
Huge thanks to Brady, CGP Grey, and Henry for their cameos.

Thank you to PhET for the Bohr model simulation: http://phet.colorado.edu/


How Does a Quantum Computer Work?

June 17th, 2013

For more on spin, check out: http://youtu.be/v1_-LsQLwkA
This video was supported by TechNYou: http://bit.ly/19bBX5G
A quantum computer works in a totally different way from a classical computer. Quantum bits or ‘qubits’ can exist in a superposition state of both zero and one simultaneously. This means that a set of two qubits can be in a superposition of four states, which therefore require four numbers to uniquely identify the state. So the amount of information stored in N qubits is two to the power of N classical bits.

Thank you to Andrea Morello and UNSW. For more info, check out: http://bit.ly/17wZ7lt


Why the Sky ISN’T Blue

May 28th, 2013

I actually have many, many more questions and answers so if you want to see them, like this video and let me know in the comments and I will edit them. Thank you for your support! I wouldn’t have gotten this far without you.


Empty Space is NOT Empty

April 30th, 2013

An atom is mostly empty space, but empty space is mostly not empty. The reason it looks empty is because electrons and photons don’t interact with the stuff that is there, quark and gluon field fluctuations.
It actually takes energy to clear out space and make a true ’empty’ vacuum. This seems incredibly counter-intuitive but we can make an analogy to a permanent magnet. When at low energies, like at room temperature, there is a magnetic field around the magnet due to the alignment of all the magnetic moments of the atoms. But if you add some energy to it by heating it, the particles gain thermal energy, which above the Curie temperature makes their magnetic moments randomly oriented and hence destroying the magnetic field. So in this case energy is needed to clear out the field, just as in the quantum vacuum.

Special thanks to Professor Derek Leinweber, find out more about his research here: http://bit.ly/ZZTKFP