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The simple physics behind a Fidget Spinner

When you want something to spin for a really long time you need to make sure that the friction does not slow it down.

And we can do this by adopting ball bearings. This is so because friction offered due to rolling is much smaller than due to sliding.

And many Fidget spinners indeed use ceramic ball bearings to keep them spinning for a long time. **

Mass Distribution

The next most crucial component is the Angular Momentum. Angular momentum is equal to the product of rotational velocity and the moment of inertia. 

And by distributing more mass towards the edge, the fidget spinner gains high moment of inertia keeping it spinning longer. 

That’s why the spinners have that weird peculiar shape.

But, Why do they feel alive ?

The angular momentum of a fidget spinner happens to point outwards from the spinner’s center.

And so to change the direction of the momentum — rotating the spinner with your fingers — you must apply a force. You push on the spinner, and the spinner pushes back on you.

That’s why a fidget spinner feels like it fights you, like it’s alive.

- Nerdist

A very fascinating toy nevertheless!

** Spin Test : Ceramic Vs Steel ball bearings

*** Fidget spinner trick shots

The United Engineering Center, 345 E. 47th Street, New York City, was headquarters to the major engineering United States engineering societies (ASCE, AIME, ASME, IEEE, AIChE and the UEF) from 1960 to 1997. In 1997, the building was sold to Donald Trump and demolished in 1998 to make room for the Trump World Tower, a 72 floor residential tower.

These 17 Women Changed The Face Of Physics

Click through to read the rest.

Iranian newspaper clip, 1968 which reads: “A quarter of Iran’s Nuclear Energy scientists are women.” The picture shows five female Iranian PhDs posing in front of Tehran’s research reactor.

A page of Willem ’s Gravesande’s 1720 book Physices Elementa Mathematica with Jan van Musschenbroek’s magic lantern, an early type of image projector,  projecting a monster. The depicted lantern is one of the oldest known to be preserved and is in the collection of Museum Boerhaave, Leiden.

Dawn O'Mara sitting on the edge of the front cockpit of a de Havilland DH82 Tiger Moth biplane, circa 1953.

One of New York Central’s “Mercury” engines in Chicago, 1936.

When you are in the combat zone, agility of a fighter jet is of utmost importance. But as an engineer, if you have already fiddled around with the wing structure your next option would be to fiddle around with the direction of the thrust.

Thrust Vectoring

Thrust vectoring is primarily used for directional control in rockets and jets. And one achieves this by manipulating the direction of thrust .

This generates the necessary moments (and forces) that enable the directional control of the aircraft. 

An aircraft traditionally has three “degrees of freedom” in aerodynamic maneuverability; pitch, yaw and roll. **

The number of “dimensions” of thrust vectoring relates directly to how many degrees of freedom can be manipulated using only the vectored engine thrust.

Therefore, 2D vectoring allows control over two degrees of freedom (typically pitch plus either roll or yaw) while 3D controls all three.

Lockheed Martin F35B

The F-35B short takeoff/vertical landing (STOVL) variant is the world’s first supersonic STOVL stealth aircraft.

It achieves STOVL by swiveling its engine 90 degrees and directing its thrust downward during take off/lvertical landing mode.

In the following gif you can witness the transition from a 90 degree tilted engine towards a forward thrust engine during flying.

Unlike other variants of the Lockheed Martin F-35 the F-35B has no landing hook. And as a result, witnessing its landing is rather pretty special.

But nevertheless, this is one of those posts which addresses a topic that has been a gold mine for research. If this sort of thing fascinated you, there have been a lot of research conducted by NASA do check them out.

Have a great day!

*Rockets - How to turn during flight ?

** Aviation 101 : Pitch Roll and Yaw

Gravitational Waves Win 2017 Nobel Prize In Physics, The Ultimate Fusion Of Theory And Experiment

“The 2017 Nobel Prize in Physics may have gone to three individuals who made an outstanding contribution to the scientific enterprise, but it’s a story about so much more than that. It’s about all the men and women over more than 100 years who’ve contributed, theoretically and experimentally and observationally, to our understanding of the precise workings of the Universe. Science is much more than a method; it’s the accumulated knowledge of the entire human enterprise, gathered and synthesized together for the betterment of everyone. While the most prestigious award has now gone to gravitational waves, the science of this phenomenon is only in its earliest stages. The best is yet to come.”

It’s official at long last: the 2017 Nobel Prize in Physics has been awarded to three individuals most responsible for the development and eventual direct detection of gravitational waves. Congratulations to Rainer Weiss, Kip Thorne, and Barry Barish, whose respective contributions to the experimental setup of gravitational wave detectors, theoretical predictions about which astrophysical events produce which signals, and the design-and-building of the modern LIGO interferometers helped make it all possible. The story of directly detecting gravitational waves is so much more, however, than the story of just these three individuals, or even than the story of their collaborators. Instead, it’s the ultimate culmination of a century of theoretical, experimental, and instrumentational work, dating back to Einstein himself. It’s a story that includes physics titans Howard Robertson, Richard Feynman, and Joseph Weber. It includes Russell Hulse and Joseph Taylor, who won a Nobel decades earlier for the indirect detection of gravitational waves. And it’s the story of over 1,000 men and women who contributed to LIGO and VIRGO, bringing us into the era of gravitational wave astronomy.

The 2017 Nobel Prize in Physics may only go to three individuals, but it’s the ultimate fusion of theory and experiment. And yes, the best is yet to come! 

Like this book but… I wish I could read the formulas without a magnifying glass! The formulas, for whatever reason, on a Kindle (I have Kindle Keyboard and Kindle Fire HD) are too small to read. I can use a magnifying glass on the Kindle Keyboard, with the Fire some are still unreadable. Go to Amazon

Well worth the money I bought the first edition, and was impressed. As a US Marine Radar Technician and engineering student, I find that so many of us in the electronics fields either never built a solid foundation in the basics of electronics, or have forgotten a lot of the fundamentals. This is a great book for correcting either of those issues. Go to Amazon

Great learning tool I got the book as a basic introduction to electrical engineering. I have messed around with some simple wireing in the past but never really had any idea what I was doing. This book was great, it had enough in depth explanation to cover my ignorance, and enough technical stuff that I had to scratch my head and re-read it a few times. I loved this book and would absolutely reccomend it to anyone looking at entering the field of electrical engineering, or even if you are just interested in becomming a little more familiar with the technical world we live in. Go to Amazon

Thank you. Thank you. Go to Amazon

Not quite for the total beginner! Grammatical and punctuation errors abound! Circuit diagrams unreadable. This is a Kindle review… Go to Amazon

Really a good interesting book Really a good interesting book. May be a good addendum to your text books to help understand the concepts better. Definitely not a text book or by any means all inclusive, but the author has a way of explaining the fundamentals in laymen’s terms, that anyone can understand. That alone is worth the price of the book and I can count the number of EE books that do that on one hand… er finger. Go to Amazon

Oh it is so informative Darren Ashby really give me so many answers to the mysteries that have always baffled and stress me out with electronics and circuits. After just enough electronics training to create confusion, the recent re-pursuit of an electronics degree feels as if it were catered to with this book. Darren Ashby goes into not only speaking of Boolean Logic in the chapter I have just finished, but he also gives the print of how the actual logic gate looks with hardware!! Its like omg! guys, omg! The thought and explanitions in this book is a great un-confuse-er with electronic circuits…….A great read Go to Amazon

Very Informative Book! This one probably one the most well written books for Electrical Engineering I have ever read. Not only would this be helpful for electrical engineers but general electricians as well. Go to Amazon

Four Stars tell a lot of the product . Entertaining style, intuitive, visual approach helps in understanding abstract concepts. Two Stars Five Stars This book and this author, I will say, … Excellent Too basic for any engineer and too vague for a beginner Five Stars Very pleased.