The Leidenfrost effect occurs when a liquid is exposed to a surface so hot that it instantly vaporizes part of the liquid. It’s typically seen with a drop of water on a very hot pan; the drop will slide around, nearly frictionless, upon a cushion of its own vapor. You can see the effect when plunging a hot object into a bath of liquid, too. This is what happens when you quickly dunk a hand in liquid nitrogen (not recommended, incidentally) or when you drop a red hot steel ball into water like above. In this case, the object is so hot that it gets encased in a layer of water vapor. If you could maintain the temperature difference necessary to keep the vapor layer intact, you could move underwater at high speeds with low drag, similar to the effects of supercavitation. (Image credit: Paul Pyro, source)

If you enjoy FYFD, please consider supporting the site by becoming a patron!

Scientists from the Laser Interferometer Gravitational-Wave Observatory (LIGO) will make a major research announcement on Thursday, at 10:30 a.m. Eastern Time, at a press conference hosted by the National Science Foundation. Unfortunately, the press conference is for media only, so there will be no live streaming events. Nevertheless, we’re skeptically excited about tomorrow. If the rumors are true, and gravitational waves have been discovered, it would mean that the most elusive prediction of Einstein’s theory of relativity is right, gravitational radiation exists, and that these waves can be detected. Finding gravitational waves would be a monumental scientific discovery, it would kick-start a new era for gravitational-wave astronomy!

Image Credit: S. Larson

sciencealert.com
Bacterial cells are actually the world's smallest 'eyeballs', scientists discover by accident
Ever feel like you're being watched?
By Peter Dockrill

In a surprise discovery, scientists have found that bacteria see the world in effectively the same way as humans, with bacterial cells acting as the equivalent of microscopic eyeballs.

British and German researchers made the finding by accident when studying aquatic cyanobacteria, which sometimes form a green film on rocks and pebbles. Scientists already knew the bacteria could perceive the position of a light source and move towards it – a phenomenon called phototaxis – but before now, no one understood how they did it.

“We noticed it accidentally, because we had cells on a surface and we were shining light from one side, in order to watch the movement towards the light,” microbiologist Conrad Mullineaux from Queen Mary University of London told Jonathan Webb at BBC News. “We suddenly saw these focused bright spots [inside the cells] and we thought, ‘bloody hell!’ Immediately, it was pretty obvious what was going on.”

What the researchers discovered when studying Synechocystis – a species of cyanobacteria found in freshwater lakes and rivers – is that their cell bodies act like a lens. When light hits the spherical surface of the cell, it refracts into a point on the other side of the cell. This triggers movement by the cell away from the focused internal spot, towards the source of the light, with the cells using tiny tentacle-like structures called pili to pull themselves forwards.

Continue Reading.

Through the  Looking Glass

Sony’s Vaio logo might seem oblivious to any onlooker at first, but on a closer inspection one might be able to uncover the rudimentary run of the mill rendition that the symbol stands for.

The VA part of the logo represents a sine wave - the basic analog signal. And IO part of the logo represents 1 0 symbolizing the digital signal.

What does it stand for?

VAIO stands for Visual Audio Intelligent Organizer and it represents the history and evolution of technology from analog to digital.


Wait, There’s more!

That power button that you find on all devices. Now that doesn’t look alien to you now, does it?

Great day! 

anonymous asked:

I love space so much and I would love to study astrophysics but alas, I couldn't do physics if my life depended on it

if you’re really considering studying space but worry about your physics check out my study and school tags, a lot of people worry about the same thing, even me and I’m already at uni :^)

Another topic from physics! I’m getting quite used to this way of making notes. Pretty, colorful and effective - what could i want more?

China surpasses Germany’s nuclear fusion milestone with record setting plasma generation

Days after the German chancellor triggered the creation of hydrogen plasma for less than a second, China has announced that one of its fusion reactors has broken the record for plasma creation.

On Friday the Chinese Academy of Sciences announced that its boffins had created the 102-second plasma burn in its Experimental Advanced Superconducting Tokamak (EAST) at Hefei, capital city of east China’s Anhui Province.

During the experiment, sensors recorded the plasma’s temperature at 50 million degrees Celsius (90 million degrees Fahrenheit).

(via China surpasses Germany’s nuclear fusion milestone with record setting plasma generation)

Feynman on Understanding Physics

Extracted form The Feynman Lectures on Physics Volume II

The physicist needs a facility in looking at problems from several points of view. The exact analysis of real physical problems is usually quite complicated and any particular physical situation may be too complicated to analyse directly by solving the differential equation. But one can still get a very good idea of the behaviour of a system if one has some feel for the character of the solution in different circumstances. Ideas such as the field lines, capacitance, resistance and inductance are, for such purposes, very useful. On the other hand, none of the heuristic models, such as field lines, is really adequate and accurate for all situations. There is only on precise way of presenting the laws, and that is by means of differential equations. 

It will take you some time to understand what should happen in different circumstances. You will have to solve the equations. Each time you solve the equations, you will learn something about the character of the solutions. To keep these solutions in mind, it will be useful also to study their meaning in terms of field lines and of other concepts. This is the way you will really “understand” the equations. That is the difference between mathematics and physics. Mathematicians, or people who have very mathematical minds, are often led astray when “studying” physics because they lose sight of the physics. They say: “Look, these differential equations - the Maxwell equations- are all there is to electrodynamics; it is admitted by the physicists that there is nothing which is not contained in the equations. The equations are complicated, but after all they are only mathematical equations and if I understand them mathematically inside out, I will understand the physics inside out.” Only it doesn’t work that way. Mathematicians who study physics with that point of view- and there have been many of them- usually make little contribution of physics and, in fact, little to mathematics. They fail because the actual physical situations in the real world are so complicated that it is necessary to have a much broader understanding of the equations. 

What is means really to understand an equation- that is, in more than a strictly mathematical sense- was described by Dirac. He said: “I understand what an equation means if I have a way of figuring out the characteristics of its solution without actually solving it.” So if we have a way of knowing what should happen in given circumstances without actually solving the equations, then we “understand” the equations, as applied to these circumstances. A physical understanding is a completely unmathematical, imprecise, and inexact thing, but absolutely necessary for a physicist.