mechanical sciences

Catching prey using Vortices

I was reading about Vortices and after hours of research online, out of the blue I stumbled upon this amazing bird. This is the Red Necked Phalarope and from the looks of it seems to have put vortices to a really productive use - catching its prey.

By rotating around ~60-80 times a minute, it produces an upward vortex that sucks out insects/bugs/crustaceans from the water, which it swiftly picks up with its beak and eats. ( This one would have aced the Fluids class for sure :D)

This is analogous to tornadoes sweeping up cars and houses along its way in an upward swirl.

Mind Blown!

** The actual dynamics of vortices of course is waay more complicated. ;)

*** There are three species of phalarope (red-necked, red/grey, and Wilson’s), and they can all feed like that.            

Dr. Tesla Discussing The Ether Space Wave Theory

“It was evident to me that wireless transmission of energy, if it could ever be accomplished, is not an invention; it is an art. Bell’s telephone, Edison’s phonograph, or my induction motor were inventions, but the wireless transmission of energy is an art that requires a great many inventions in combination.

“We are living on a planet that is rushing through space; this planet is partly conducting and partly insulating. If it were all conducting, or if it were all insulating, we could not transmit energy without wire. It is only because it is partly conducting and partly insulating that a glorious future for man is reserved through the application of this art.”

–Nikola Tesla

(From a pre-hearing interview with Nikola Tesla and his legal counsel in 1916 to protect his radio patents from the Guglielmo Marconi and the Marconi Company.)

[Fig. 1]:
“We are living on a planet of well-nigh inconceivable dimensions, surrounded by a layer of insulating air above which is a rarefied and conducting atmosphere. This is providential, for if all the air were conducting the transmission of electrical energy thru the natural media would be impossible.” –NT

[Fig. 2]:
“My early experiments have shown that currents of high frequency and great tension readily pass thru an atmosphere but moderately rarefied, so that the insulating stratum is reduced to a small thickness as will be evident by inspection of [Fig. 2], in which a part of the earth and its gaseous envelope is shown to scale. If the radius of the sphere is 12½”, then the non-conducting layer is only 1/64″ thick and it will be obvious that the Hertzian rays cannot traverse so thin a crack between two conducting surfaces for any considerable distance, without being absorbed.” –NT

“Famous Scientific Illusions.” Electrical Experimenter, February, 1919.
nature.com
The quest to crystallize time
Bizarre forms of matter called time crystals were supposed to be physically impossible. Now they’re not.

Christopher Monroe spends his life poking at atoms with light. He arranges them into rings and chains and then massages them with lasers to explore their properties and make basic quantum computers. Last year, he decided to try something seemingly impossible: to create a time crystal.

The name sounds like a prop from Doctor Who, but it has roots in actual physics. Time crystals are hypothetical structures that pulse without requiring any energy — like a ticking clock that never needs winding. The pattern repeats in time in much the same way that the atoms of a crystal repeat in space. The idea was so challenging that when Nobel prizewinning physicist Frank Wilczek proposed the provocative concept1 in 2012, other researchers quickly proved there was no way to create time crystals.

But there was a loophole — and researchers in a separate branch of physics found a way to exploit the gap. Monroe, a physicist at the University of Maryland in College Park, and his team used chains of atoms they had constructed for other purposes to make a version of a time crystal2 (see ‘How to create a time crystal’). “I would say it sort of fell in our laps,” says Monroe.

And a group led by researchers at Harvard University in Cambridge, Massachusetts, independently fashioned time crystals out of 'dirty’ diamonds3. Both versions, which are published this week in Nature, are considered time crystals, but not how Wilczek originally imagined. “It’s less weird than the first idea, but it’s still fricking weird,” says Norman Yao, a physicist at the University of California, Berkeley, and an author on both papers.

Continue Reading.

A note on Vibration and Washing Machines

If you have taken a sneak peak into a washing machine then you might have noticed that it has a concrete block inside (also why they are heavy).

Their primary purpose is to absorb vibrations caused by the rotating body (in this case the drum) and keep the machine stable.

But this begs the question of what would happen if it didn’t have the concrete dampener. The above gif from the secret life of machines shows you exactly that.

With no cushion to dampen out the vibration, the machine propels forward from the unbalanced linear and torsional forces and eventually breaks down.

Have a great day!

**

Balancing of rotating masses

Hello everyone.

Apologies for the long/unexplained absence. I’ve not been doing very well recently and I haven’t quite had the time to be posting. However, a small update is that I’m struggling very much with my mental health but my studies are going very well. I just wanted to thank you all for your kindness and support and I will try update more regularly from now on!

I hope you are all well and looking after yourself, and I’m sending love, hugs and good study vibes 💗

10

Ask Ethan: What’s The Quantum Reason That Sodium And Water React?

“Which forces drive chemical reactions, and what takes place on a quantum level? In particular, what happens when water interacts with sodium?”

Every beginning chemistry student learns what happens when you put a chunk of sodium metal into water: you get an extremely violent reaction out. The sodium and water bubble and fizz, and sometimes even a flame or an outright combustion reaction is produced. This isn’t exclusive to sodium, either, but occurs for lithium, potassium, rubidium, cesium and more. We can describe these chemical reactions using basic chemistry, of course, but there’s a more fundamental reason it occurs: the laws of quantum mechanics. By combining the laws of electromagnetism with the Pauli exclusion principle and the shapes of electron orbitals, we can understand the full step-by-step process by which this occurs. Thanks to these laws, a reaction that had been described for hundreds of years can now finally be fully explained.

What’s the quantum reason sodium and water react? Find out on this edition of Ask Ethan!

flickr

… push-button transmission! by James Vaughan