Objects hang heavy side down, but what happens when you spin an asymmetrically weighted disk - well the heavy part actually rises to the top. Why is this?

1, 2, 3 A song about 'lectricity
because it powers our lives
makes it possible for us to thrive

because it powers our lives
makes it possible for us to thrive

Oh, 4, 5, 6, volts of potential difference
makes electrons go round
if the circuit is complete and sound

Circuit's closed
Voltage There
Current Flows
Power Everywhere

We use AC,
in factories
and homes because we can transform it
High voltage
transmits with lower loss
but low voltage is best for safety
I said what is electricity?

Well, so 1,2,3 a song about 'lectricty
because it powers our lives
makes it possible for us to thrive

because it powers our lives
makes it possible for us to thrive

Oh, 4,5,6 volts of potential difference
makes electrons go round if the circuit is complete and sound

Heat makes steam
turns turbines
and a magnet in
coils of wires

We use AC,
in factories
and homes because we can transform it
High voltage
transmits with lower loss
but low voltage is best for safety
I said what is electricity?

Oh yeah, Oh yeah, C'mon!
How'd it be
no energy
of the electrical persuasion
I know we'd
have no computers
no internet or mobile phones yeah
Powers the world
Makes the world
We need electricity yeah

A song about Gravity set to the tune of John Mayer's Gravity.

Gravity is working with me
And Gravity, keeps me on the ground

All mass attracts all other mass
a force proportional to mass one and two
and inversely to the distance between them squared

Oh, gravity is working with me
and gravity, makes apples fall to ground

Oh twice the mass has twice the pull
but the force on each is still equal
It keeps the moon and the satellites
going round

Oh twice the mass has twice the pull
but the force on each is still equal
It keeps the moon and the satellites
going round

Oh gravity, the force that makes weight on me
Woah, gravity, now general relativity (how can that be?)

The force between us all is
The force between us all is
The force between us all is
Gravity between us all is
Gravity between us all is
Gravity between gravity between us all is

Origami is inspiring a plethora of new engineering designs. Try yourself: https://ve42.co/Origami
Thanks Audible! Start listening with a 30-day trial and your first audiobook, plus two Audible Originals free when you go to https://audible.com/veritasium or text veritasium to 500500

Huge thanks to:
Dr. Robert Lang https://langorigami.com
Prof. Larry Howell https://www.compliantmechanisms.byu.edu/

On first glance it's surprising that origami -- a centuries old art of folding paper to achieve particular aesthetics -- is applicable to engineering. But upon closer consideration there are a lot of reasons methods developed for paper folding are also applicable to engineering: origami allows you to take a flat sheet of material and convert it to almost any shape only by folding. Plus for large flat structures, origami provides a way of shrinking dimensions while ensuring simply deployment - this is particularly useful for solar arrays in space applications. Furthermore, motions designed to take advantage of the flexibility of paper can also be used to form compliant mechanisms for engineering like the kaleidocycle. Since the principles of origami are scalable, mechanisms can also be dramatically miniaturized.

Some of the work shown is based upon work supported by the National Science Foundation and the Air Force Office of Scientific Research under Grant No. EFRI-ODISSEI-1240417. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation.

Special thanks to Patreon supporters:
Alfred Wallace, Arjun Chakroborty, Bryan Baker, Chris Vargas, Chuck Lauer Vose, DALE HORNE, Donal Botkin, halyoav, James Knight, Jasper Xin, Joar Wandborg, Kevin Beavers, kkm, Leah Howard, Lyvann Ferrusca, Michael Krugman, Noel Braganza, Pindex, Ron Neal, Sam Lutfi, Stan Presolski, Tige Thorman

Edited by
Jonny Hyman, Isaac Frame, and Derek Muller

Music by
Jonny Hyman

Evidence Facebook's revenue is based on fake likes.
My first vid on the problem with Facebook: http://bit.ly/1dXudqY
I know first-hand that Facebook's advertising model is deeply flawed. When I paid to promote my page I gained 80,000 followers in developing countries who didn't care about Veritasium (but I wasn't aware of this at the time). They drove my reach and engagement numbers down, basically rendering the page useless. I am not the only one who has experienced this. Rory Cellan-Jones had the same luck with Virtual Bagel: http://www.bbc.co.uk/news/technology-18819338

The US Department of State spent $630,000 to acquire 2 million page likes and then realized only 2% were engaged. http://wapo.st/1glcyZo

I thought I would demonstrate that the same thing is still happening now by creating Virtual Cat (http://www.facebook.com/MyVirtualCat). I was surprised to discover something worse - false likes are coming from everywhere, including Canada, the US, the UK, and Australia. So even those carefully targeting their campaigns are likely being duped into spending real money on fake followers. Then when they try to reach their followers they have to pay again.

And it's possible to be a victim of fake likes without even advertising. Pages that end up on Facebook's "International Suggested Pages" are also easy targets for click-farms seeking to diversify their likes. http://tnw.co/NsflrC

Thanks to Henry, Grey, and Nessy for feedback on earlier drafts of this video.

Veritasium is a channel of science and engineering videos featuring experiments, expert interviews, cool demos, and discussions with the public about everything science.
Clips featured in this video:
Trees are Freaking Awesome - http://bit.ly/TFilQ8
Gyroscopic Precession - http://bit.ly/U4e8HQ
Can We Go The Speed of Light? (Principle of Relativity) - http://bit.ly/X1BlXZ
Where Does The Sun Get Its Energy? - http://bit.ly/125jbeM
Where Do Trees Get Their Mass? - http://bit.ly/11AA817
What Is A Candle Flame Made Of? - http://bit.ly/Q3enCb
Levitating Barbecue (Electromagnetic Induction) - http://bit.ly/SWgOWh
Imploding Drum - http://bit.ly/125jG8B
Microwave Grape Plasma - http://bit.ly/QkCwUt
Spinning Tube Trick - http://bit.ly/Va43Z6
Spinning Disk Trick - http://bit.ly/14MSKsT
Why Do You Make People Look Stupid? - http://bit.ly/12Fmlpl
Awesome HD Slinky Slow-Mo - http://bit.ly/TRa4sE
Subscribe to Veritasium - http://bit.ly/YSWpWm

Mosquitoes are attracted to me and it's likely due to my genes.
This video is sponsored by 23andMe https://23andme.com/veritasium
Huge thanks to Prof. Immo Hansen and team: http://ve42.co/hansen

References:
Genome Wide Association Study for self-reported mosquito attractiveness:
http://ve42.co/MossieGWAS

The twin study showing correlated attractiveness is stronger for identical twins:
http://ve42.co/MossieTwins

Some things we know make mosquitoes more attracted to you:
Exercising, higher metabolism, higher body temperature, more body odor, being pregnant, type O blood, infrequent bathing, lactic acid, ammonia, acetone.

There are a number of folk remedies people believe protect them from mosquito bites like drinking alcohol, eating garlic, or taking vitamin B. These do not appear to provide any benefit in lab studies and in fact drinking alcohol is associated with increased mosquito activity because it causes blood vessels near the surface of the skin to dilate.

And apparently some of your attractiveness to mosquitos is simply genetic. This may be mediated through your immune system, which is what a lot of the genes identified were associated with.

Molecular models are microSnatoms: http://snatoms.com

Filming in New Mexico by Raquel Nuno
Animations by Jacqui Robertson

The opinions and conclusions drawn in this video are those of Veritasium and not 23andMe.

It takes the moon about 27 days to orbit the Earth. What makes it go round? It is the gravitational attraction of the Earth on the moon. Due to the moon's velocity, the Earth keeps pulling the moon towards it without the moon actually getting closer to the Earth. This is similar to how satellites orbit the Earth.

Tiny robots activated by magnetic fields may be used in future biomedical procedures. Start listening to Audible with a 30-day trial and your first audiobook, plus two Audible Originals free when you go to http://audible.com/veritasium or text veritasium to 500500

Huge thanks to:
Dr. Eric Diller, Assistant Professor of Mechanical Engineering at the University of Toronto
http://microrobotics.mie.utoronto.ca

Research Referenced in this video:

T. Xu, J. Zhang, M. Salehizadeh, O. Onaizah and E. Diller, Millimeter-scale flexible robots with programmable three-dimensional magnetization and motions. Science Robotics. 4, eaav4494 (2019).
http://robotics.sciencemag.org..../lookup/doi/10.1126/

H. Xie, M. Sun, X. Fan, Z. Lin, W. Chen, L. Wang, L. Dong, and Q. He, Reconfigurable magnetic microrobot swarm: Multimode transformation, locomotion, and manipulation. Science Robotics. 4, eaav8006 (2019).
http://robotics.sciencemag.org..../lookup/doi/10.1126/

G. Hwang, A. J. Paula, E. E. Hunter, Y. Liu, A. Babeer, B. Karabucak, K Stebe, V. Kumar, E. Steager, and H. Koo, Catalytic antimicrobial robots for biofilm eradication. Science Robotics. 4, eeaw2388 (2019).
http://robotics.sciencemag.org..../lookup/doi/10.1126/

Special thanks to Patreon supporters:
Donal Botkin, Michael Krugman, Ron Neal, Stan Presolski, Terrance Shepherd, Penward Rhyme

Music by Kevin MacLeod http://incompetech.com "Marty Gots a Plan" "March of the Spoons"

In Queenstown, New Zealand, I jumped off the Kawarau Bridge - the site of the first bungy jump. It was a thrilling experience, preceded by a terrifying, gut-wrenching half hour wait. All in all an awesome adventure, even if the woman fitting my harness didn't know the first thing about the acceleration of free-falling bodies.

When a grape is cut nearly in half and placed in a microwave, plasma is produced. Please use caution if attempting this experiment: don't leave the microwave on for too long, make sure the area is well ventilated, and stand back. Remember the contents will be very hot afterwards.

Smarter Every Day Collaboration video: http://youtu.be/riwc3UgPaHw
The Veritasium treatment of the final transit of Venus this century. The weather behaved for some key moments allowing me to observe Venus passing across the disk of the sun. The transit of Venus is steeped in historical significance. Observations of the transit in 1769 led to the first really accurate calculation of the Earth-Sun distance (or one astronomical unit AU). Since Cook was in Tahiti he then mapped the East coast of Australia and parts of New Zealand.

The aurora borealis or northern lights is one of the most spectacular natural displays on the planet. Theories about its origins have been debated for centuries and common misconceptions persist that the aurora is the sun's rays scattered off ice crystals in the high atmosphere. In truth, the light is created more than 100km above Earth's surface as high speed electrons and protons ejected from the sun in a solar flare or coronal mass ejection collide with air molecules in the upper atmosphere. The charged particles from the sun excite air molecules which then de-excite by emitting light. The display is most common around the north and south poles because the Earth's magnetic field deflects the solar wind from the equator to the poles. Here the magnetic field dips towards the Earth's surface, channeling the charged particles into the atmosphere.

Music is by Kevin MacLeod http://incompetech.com, the song is called Mirage

More about the Alaska Trip: http://education.projectaether.org

Channel 10 Breakfast: http://www.tenbreakfast.com.au (6-9am weekdays in Australia)

March 26 segment on live TV talking about solar storms and my upcoming trip to the Great White North. As you watch this I will probably be on a plane high over the pacific.
PS a student recently told me that my hair to beard ratio is a bit off and watching this clip I tend to agree. However, it is still -20 C at night in Alaska so I'll need all the insulation I can get.

Right: https://www.youtube.com/watch?v=AS9OXzSRBMQ
Left: http://www.youtube.com/watch?v=FWQ-HJ4oGKQ
It Depends: https://www.youtube.com/watch?v=R3GHiMOHEy8
What happens when nylon rope is wound around a spool and pulled horizontally to the right? Will the spool go to the right, to the left, or does it depend on how the rope is pulled?

To celebrate the announcement of the discovery of a particle consistent with the Higgs Boson at the LHC, I took to the streets with Vi Hart to give out free Higgs. Now giving out a subatomic particle, especially the Higgs, would have been incredibly difficult so instead we gave out hand-drawn cards of the Standard Model, our current best theory of all matter particles in the universe and their iteractions (now with Higgs!). We also offered a hug with an integer spin, usually 1 or 2 (and in rare cases 0). This is a way of showing others that you care about the Higgs Boson.

How should we depict an atom? Like a solar system with electrons orbiting the nucleus on hula hoop orbits? That idea is so last century! Bosi takes us into the quantum world, where an electron's position and velocity aren't well defined - all we can calculate are the probabilities e.g. of finding an electron at different points in space. When we do that, we find electrons do not neccessarily occupy circles or spheres in space. Rather their probability densities make all sorts of interesting shapes from the dumbell to the peanut with the donut around it.

I'm going to London! And I'm leading a team of YouTubers. For the next few weeks we will all be doing videos themed around the Olympics so I'm tackling the science of sport and science in and around London.

The Team!
HOWRIDICULOUS: http://bit.ly/LtFzpW
APPCHAT: http://bit.ly/NxAMlX
ERIKAANEAR: http://bit.ly/MdyUzQ
MINUTEPHYSICS: http://bit.ly/Muh6CC
EFIT30: http://bit.ly/O4CMme

2VERITASIUM http://youtube.com/2veritasium

Music by Alankeys86 and Kevin McLeod (Incompetech.com)

For the London 2012 Summer Olympics creators from all over the world are taking over YouTube with the most awesome Olympics videos ever. Go to YouTube.com/CreatorHub to see all the amazing gold medal videos.

If the sun were entirely made of protons, how many would there be in the sun? How can this be worked out using the Google search field?

What happens when a slinky that has been extended under its own weight is released? How does it fall to the ground? Answer link: http://www.youtube.com/watch?v=eCMmmEEyOO0