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Engineering Makes the World Go Around

Engineering is everywhere. It has provided you with buildings, transportation, schools, paper, and even your computer you are using to view this page. It is knowledge that makes the world go around. No? O.K., it's the money that makes the world go around, and engineering provides an extra boost to let it go around fashionably smoother. And if you really wanna be brutally practical, it eases the trouble for getting a job if you have a degree in it.

The most beautiful part of engineering is that you don't really have to memorize much once you have understood the basics. Moreover, most of concepts are highly logical that you understand it naturally once you are exposed to it. For example, even a slightly complicated concept as Escape Velocity, minimum speed required to escape from the gravity field of a planet, is easily understood once one understands the concept.


Vescape2 = 2 G M / r
The basic concept here is that 'An object has to be given with enough energy initially to overcome the negative work to be done by the gravitational force while it's escaping.' The positive energy to be used as an initial boost here, is called kinetic energy. One should be able to find following equations easily in a common physics book.


Ekinetic = m v2 / 2

Fgravity = G M m / r2

   where, m is mass of an object,
          v is velocity of the object,
          G is a gravitational constant (some number),
          M is mass of a planet,
          r is distance between the two, center to center.
What we are trying to do here is not to memorize these equations, but to make some sense out of the above symbolic expressions.

Well, most of us understand that heavier objects are harder to move (or to accelerate). If something's hard to do, it just will take more energy to perform that task. So you wonder why kinetic energy is proportional to v2 instead of v, hay? Well, you will just have to accept this one as a law of physics. Lamborghini, for instance, costs about 1/4 a million for a regular model (mid 90's last millenuim). However, if you want to purchase a model that runs 10 or 20 MPH faster, it'll cost you 1/2 million because it requires twice as much horsepower to run that fast. Surprising, eh?

 


"If I have bored you by now, please feel free to browse back."
The concept of gravitational force comes from Albert Einstein's theory of relativity which states that all masses attract each other. Hence, gravity is proportional to masses of the two, and it drops dramatically when the distance between them increases. It's sort of like magnates. When the two are far apart, they wouldn't even budge but a small decrease in distance will allow them to collide at a relatively high speed.

If you understood steps so far, the rest is easy. work (or energy equals to force times distance that the force was used to perform the work. Hence, after performing an integration;

Egravity = G M m / r2 x r
Above equation is the minimum energy required to move an object out of a gravity field. So, simple set, Ekinetic = Egravity. After some simplifications, we should get this fantastic outcome of;
Vescape2 = 2 G M / r
Wasn't that easy? Or maybe I got a little carried away. The point I tried to make across here was that engineering can be very simple and logical when you study it though it might look awfully complicated when you jump into an advanced one without having fundamentals to understand it.

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