–Nikola Tesla

Technical drawings of an F4U Corsair

Poor Alex :(. If you don’t get it, you can’t be an engineer 😂.

F1 is more than just racing, it is an engineering battle. In this gif you can see the absolute control of wing tip vortices generated from the front wing. This is just an example to show the extreme aerodynamics that these vehicles are engineered for.

Have a great day!

* What are wing tip vortices ?

** Smoke angels and wing tip vortices

     Smithsonian’s National Air & Space Museum Udvar-Hazy Center in Chantilly, Virginia, offers the unique sight of a complete Mercury spacecraft. Many of these spacecraft are available for viewing all over the United States, but this one is special because it did not fly.

     During the course of a Mercury flight, several parts of the spacecraft are jettisoned and not recovered, including the retro package. This piece of equipment is visible here in my photos as the striped metal object strapped to the bottom of the heat shield. This small cluster of solid rocket motors was responsible for the safe return of the astronaut from space, making just enough thrust to change the shape of the orbit so that it would meet the atmosphere and use aerobraking for a ballistic reentry.

     If this package had not fired properly, the astronaut would be faced with the dire situation of being stuck in orbit. Fortunately, this never happened in real life, but it was captured in the fanciful novel “Marooned” by Martin Cardin, in which a NASA astronaut was stranded on orbit after his retro rockets failed. When the book was released in 1964, it was so influential that it actually changed procedures for Mercury’s follow on program Project Gemini, adding more redundancy to the spacecraft’s reentry flight profile.

     Alan Shepard, the first American in space and later Apollo 14 moonwalker, didn’t fail to notice that there was a leftover spacecraft at the end of the Mercury program. He lobbied for a second Mercury flight in this ship, speaking personally to both NASA Administrator James Webb and President John Kennedy about this flight. He told them his idea of an “open ended” mission in which they would keep him in orbit indefinitely until there was a malfunction or consumables began to run out. Webb stated (and Kennedy agreed) that it was more important to shelve the Mercury spacecraft in order to jump start the more capable Gemini Program. Thus, we now have this whole Mercury on display for future generations to appreciate.

The three stages before an exam. 😂

Why is Glass Transparent?

We are now in ‘The Glass Age’. It is impossible to imagine a world without glass. From Mobile phones to glass panels, it is omnipresent.

Such a pivotal role does Glass play in our day to day to lives, but yet when confronted with the question - “why is glass transparent?”, we are speechless! But hey! This post is dedicated to answering that burning question.

How do we see things ?

Lights travels in straight lines. When light hits an object, it bounces off other objects (reflects) and enters our eyes. And this information is processed by our brain and this is how we see the object.

An atomic interlude.

You may know that an Atom consists of a nucleus with electrons orbiting around it. These electrons are confined to a trajectory known as an Orbit. And there exists a gap between two subsequent orbits where no electron can exist. Known as an energy-gap or a band gap( Band gap ).

And for an electron to jump from one orbit to another:

It must gain energy and jump to a higher level. ( Away from the nucleus )

It must lose energy and jump to a lower level. ( Closer to the nucleus)

The energy to make such transitions is provided by light.

What decides whether an object is Transparent, Translucent or opaque?

Imagine you are now a photon. And you are in a collision course with a material.There are three possible outcomes:

The substance absorbs the photon. This occurs when the photon gives up its energy to an electron located in the material. Armed with this extra energy, the electron is able to move to a higher energy level, while the photon disappears.

The substance reflects the photon. To do this, the photon gives up its energy to the material, but a photon of identical energy is emitted.

The substance allows the photon to pass through unchanged. Known as transmission, this happens because the photon doesn’t interact with any electron and continues its journey until it interacts with another object.

Glass, of course, falls into this last category. Photons pass through the material because they don’t have sufficient energy to excite a glass electron to a higher energy level. And due to this, we are able to see through glass!

If the material absorbs the photon, it is said to be opaque. And if it allows some photon to pass through and others get absorbed, the material is termed Translucent.

Smart Glass.

Glass does not necessarily have to transparent/ translucent/ opaque all the time.

Smart glass  is glass whose light transmission properties are altered when voltage, light or heat is applied. Generally, the glass changes from translucent to transparent, changing from blocking some (or all) wavelengths of light to letting light pass through.

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.

charles babbage: father of the computer (1970)

Hydro Robotics! 1/3

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