NMR

-Today we'll talk about NMR(small introduction).


"What does NMR stand for?"

-NMR stands for nuclear magnetic resonance. It is the property of a molecule under a magnetic field to be able to absorb electromagnetic radiation in the range of radio-frequencies defined by the characteristics of the sample.


"Ok... What's a molecule? What's a magnetic field? What's an electromagnetic radiation? What's a radio-frequency? What's life?"

-Yo it's easy! But Che doesn't have the time to teach you all of that stuff... But he will show you shinny pictures so that you might understand:

-A molecule!

-The elctromagnetic radiation spectrum
which includes the radio wave frequencies
on the far right.

-A magnetic field!

-Life!

Ok! I hope you got all that!

"More or less yeah... So what do what do we do with NMR anyways?"

-Well, we can make a NMR spectrum! Since, like mentioned earlier, the degree of electro-magnetic absorption is regulated by the characteristics of the nucleus present in a molecule, we could therefore map out the molecule itself by observing the effects of the degree of absorption. Basically, when a proton is subject to a magnetic field, it starts resonating. The frequency at which it will resonate is affected by the property of the proton and the effects of the other atoms surrounding the proton. So, if we compare the resonance frequency of the proton when it is surrounded by the atoms of the molecule we are trying to map out to the proton when it is not surrounded by anything, we get the chemical shift. This chemical shift is what we observe in a NMR spectrum.

"Ok... I'm not sure I get why it resonates but I understand the chemical shift. How does a NMR spectrum looks like anyways? "

-Well, it looks like this crap:

Pretty simple huh!

"Hmmm... I'm not sure I understand how to interpret it..."

-Yo! It's easy! But that will be a lesson for another time... Maybe! For now, just remember that we can use NMR spectroscopy to help us map out the structure of a molecule. Other techniques such as infrared spectroscopy and mass spectrometry can also be used.

Anyways, that will be all for now. Hope you learned something!

The Michelson-Morley Experiment! (Part 2)

-Ok kids, today we'll finish talking about the Michelson-Morley experiment! Please read the first part before that one or you won't understand shit! (unless you actually already know all that stuff in which case you should stop reading right now...)

"Ok... Please continue"

-Ok. Remember that we have 2 beams going in 2 different directions at 2 different speed. Both of them are gonna hit a mirror and get reflected again. Lets call the Half-silvered mirror in the center M1, the mirror on top M2 and the mirror to the far right M3. Both light should go at different speed because of the ether (like we said earlier). So when they return to M1, they will return at different time. This time difference between the 2 light beams that are colliding with each other will cause the production an interference pattern!

"Hmmm... What's an interference pattern?"

-Yo! It's easy! But Che doesn't have the time to explain all of this to you. So he will only show you what an interference pattern looks like:

Hope you got that!

"Hmmm...Not sure but ok!"

-Ok. Now, what if we turn the table 90 degree around so that the beam exchange roles? That is, the beam that was perpendicular now go in the same direction of the ether and the other beam now is perpendicular. What will happen is that a shift in the interference pattern will occur because this will result in a net time difference compared to previously. Che won't bore you with the equations that calculate this shift (he's already boring you enough!).

"Ok, so this whole thing was to check the shift in the interference pattern right? What next?"

-Well... They didn't observe any shift! (dum dum dum!) Why? Because what they thought was wrong! The ether they spoke of doesn't really exist. Einstein explains it all in his postulates of special relativity but that is a story for another time maybe!

Hope you learned something! Next time, Che will try to talk about something simpler!

The Michelson-Morley Experiment!

So today we will talk about the Michelson-Morley experiment!

''What is this?''

-Well it was an experiment that was made to try and detect the small changes in the speed of light with motion of an observer through the ether. It was performed in 1887 by Albert A. Michelson and Edward W. Morley (obviously!).

''Ok! But what exactly is the Ether and why is that crap important? ''

-Well, during this time, physicists believed that light was a form of wave. Like all kind of waves, it needs a medium to move or propagate through. For example, a water wave needs... water! This is the frame in which water waves move through. Well back in the days they thought that light would propagate through the ether! The ether would have been some kind of medium present everywhere! Right now, you would have been surrounded by ether. Don't worry, it doesn't bite...

''Ok... Now what? ''

-Well lets say you're chilling on earth (like Che is), since the earth is moving at 30 km/s around the sun, we could say that the ether is moving pass you at -30km/s from your point of view. Lets make an analogy here to make it simpler: if the earth is a moving car going straightforward at 30km/s (yeah that's a fast car...) and you are in that moving car(holy shit!), from your point of view, the road would be passing by you at -30km/s. In our analogy, the ether would be the road. Got it? Easy enough right? Che thinks so! Also, Che wants you to remember that the speed of light in free space (or c) is 3 x 10 power 8 m/s.
 
''Ok ok! So what about the experiment? ''

-Well Michelson and Morley made this crap:

                                                       <--------------          Ether movement


Lets say you're in front of this thing and you're watching through the telescope. From your point of view, the Ether would be passing by you at the speed of the earth in the direction shown. Light is produced from the light source. It goes at speed "c" (the speed of light in free space). Since light travels through the ether and the ether is passing by in the opposite direction at the speed of the earth, the speed of light should be "c - speed of the ether" right? The same way that if you're running in an escalator at speed "v" and the escalator is moving in the opposite direction at speed "v2", your total speed from the view point of an observer not on the escalator would be "v-v2". Got that? K. When light is reflected to the half-silvered mirror, it will split in 2 directions. One in the direction opposite of the Ether going at "c-speed of the ether" and the other perpendicular to the ether going at the (c^2 - ''speed of the ether''^2)^1/2 !

''Hmm wait... I don't get how you got the speed of the light beam moving perpendicular to the ether?''

-Yo! It's easy! Remember your good friend Pythagoreas and his Pythagorean theorem? I hope you do! I also hope you know a bit about vectors. Che doesn't have the time to teach you all this stuff right now. But, he will show you how he got it:

Hope you got that!

''Hmmm ok... I think I got it... Now back to the experiment please!''


-Well that will be all for now! Che will explain the rest in his next post! So make sure you tune in for the exciting conclusion of the experiment!

viva la educacion!

Che will teach you stuff,,, Good stuff!

 

Hello everyone!

So I finally started blogging. I was actually gonna code the blog myself but I decided to take the lazy route... For now at least! Indeed, in the near future, I fully intend to code it all and go through the process of getting someone to host it and etc.

Anyways! What will this blog be about you might ask? Well Che will teach you random stuff! Hopefully you will learn something out of it you fools!

Why Che? Well because I had trouble coming up with a name for the blog since everything was already taken. So I came up with this random name mostly because there's a picture of Che hanging on my wall. I hope he won't mind!