Fiber Optics

What the big deal anyway? Isn't that just like glass tubes that emit really cool lights when you cut them? More than that, actually, fiber optic cables are the reason why we can connect to the internet, talk to people over long distances and enjoy cable TV. They are also used in medical imaging and mechanical engineering inspection.

How do they transport information anyway?

First of all, we have to know what are the parts of an optic fiber.
Core - this is where the signals travel
Cladding - the thing that reflects signals bck into the core
Buffer coating - outer covering and protection from harsh elements such as moisture which
can destroy the connection
Jacket - holds single optic fiber together



The key here is internal reflection. Yes, reflection *groan*. The information is transmitted as signals, see? So, have you seen a light from laser? The light that goes in a straight path? If you turned it on in a room full of mirrors, the light bounces of to the next mirror, to the next one, so on, so forth, right? Well, signals are like that; they look like "concentrated light rays". Bouncing off the cladding into the core to travel great distances. Th principle used is total internal reflection.

Um... For the meantime, I'll try to understand this principle and tell you about it next time. I need to study for the exams... Ehenh..

Lenses

Steps for Ray Method of Converging Lenses:

1. Draw the first ray parallel to the principal axis. Draw the second ray passing through the vertex. Draw the third ray passing through the focal point in front of the mirror.

2. Based on the three laws of refraction for converging lenses, the ray of refraction for the first ray of incidence must pass through the focal point at the back of the lens, the second ray of incidence must travel a straight line and the thord ray of incidence must form a ray os rafraction parallel to the principal axis.3. The point of intersection is the tip of the object. Just draw a perpendicular line connecting the point of intersection and the principal axis.

Note: 2F is equal to C, so that object is beyond C. To have an idea of what the image of an object placed on another location would look like, just scroll down.

Steps for Ray Method for Diverging Lenses:
1. From the tip of the object, draw the first ray parallel to the principal axis. Draw a second ray that if extended would pass through the focal point of the back side of the mirror. Draw a third ray passing through the vertex.

2. Based on the three laws of refraction for diverging lenses, the ray of refraction for the first incident ray should be going up, tilted to the back side and if extended, would pass through the focal point of the front side of the lens. For the second ray, its ray of refraction must be parallel to the principal axis. For the third ray, it just goes like a straight line.
3. To get an intersection, jut extend the rays of refraction, thet connect the intersection to the principal axis with a perpendicular line, and tadah!!!! There's your image!
credits for the pictures goes to: http://www.glenbrook.k12.il.us/gbssci/phys/Class/refrn/u14l5ea.html

The light got snuffed out....

Geometric Optics. Heck, I was never good at Geometry. Starting out on concave and convex mirrors. It looked hard to understand at first but it seems a little bit easier now. For the sake of achieving enlightment! I can do this! >Yeah!!<

Here are some important terms to remember:

> center (C) - the center of the spherical mirror

>focal point (F) - the point between the center and the mirror

>vertex - middle part of the mirror

>principal axis - the horizontal line drawn from the vertex of the mirror

Steps for the Ray Diagram of Concave Mirrors:
1. From the tip of the object, draw a line parallel to the principal axis to the mirror. Then, draw another line from the tip of the object to the mirror but this time, the line must pass through the focal point.

2. From the first incident ray, draw a line passing through the focal point (as by the one of the laws of reflection of concave mirrors). From the second incident ray, draw a line parallel to the principal axis.

3. The point where the two rays of reflection intersect is where the tip of the image is. Just draw a perpendicular line connecting the point of intersection and the principal axis and tadah!!! We have an image! That's an example of an object located beyond C. The following pictures are for other locations of the object:

Note: You can extend the reflected rays until you get an intersection.

Steps for Ray Method of Convex Mirrors:

1. Draw a line parallel to the principal axis from the tip of the object to the mirror. Draw another line (that if extended, would pass through the focal point, which in this case, would be on the other side of the mirror) to the mirror. 2. As by the two laws of reflection of convex mirrors, from the first incident ray, draw a line straight up or perpendicular to the principal axis. From the point of the second incident ray touching the mirror, draw a line parallel to the principal axis. 3. To get an intersection, extend the rays.

4. The point of intersection is the tip of the object. Just draw a perpendicular line connecting it and the principal axis.

credits for the pictures go to: http://www.physicsclassroom.com/Class/refln/U13L4b.html

Happy Days are Here Again

I do so absolutely LOVE this week!!! I'm having a great time! Well, the "family day" was cancelled. We are studying Optics, which so far, is my favorite topic. Quiz one on Optics: 15out of15 (well it was a review). And it was the first time i understood the lessons one week straight! >Hyper mode< If this keeps up, I'll be high till the exams on August.

Seven Days

Day 1: <6-25> Quiz. I never thought that I could do it but I got 5 out of 5! I did it! Gosh, I think I'm gonna cry..

Day 2: <6-26> Quiz. Three out of five this time. Drat... Failed. Our lesson for today was the speed of waves on a string. You get it by getting the square root of the tension over mu. *Mu is a Greek letter which is equal to mass over length.

Day 3: <6-27> First quiz for the day, I got 2 out of five because I got the formulas the other way around. *idiot* Hakk!! He knows! He knows! Sir Mendoza knows our names! *time to wear masks and/or hide!* Second quiz for the day I got five out of five.

Day 4: <6-28> First time anybody (probably) ever saw Mr. Mendoza not smiling. Ohhhh... The atmosphere was creepier than before, let me tell you.. We did an activity about waves: drawing the effects when destructive or constructive waves meet.

Day 5: <6-29> Just the checking of the activity yesterday.

Day 6: <7-2> Sound Waves. Harder, but fun nonetheless. To get the speed of a sound wave get the square root of the elastic property over inertial property. The elastic property can be the Bulk modulus (for speed of sound waves in liquids) or Young's modulus (for speed of sound waves in solids). The inertial property, which is represented by "rho", is also the density of the medium.

Day 7: <7-3> Brain-bleeding practice.

Of Mirrors, Waves, and Illusions....

Now I wanna look back...

Remember: Passing is ALWAYS 85%!! SO Do your best! Fight! Review!

The project was given last Friday. "Life of a Mirror" music video. Cool...

Today is My Lucky Day

A Parade of Miracles passed and showered me with their confetti of good luck. A lot of good things happened today.

I understood the lesson (finally!) AND got a perfect score on the quiz (5 out of 5, a personal record). The lesson was about the Law of Reflection. It was so fun...

I'm looking forward to tomorrow!