<body><script type="text/javascript"> function setAttributeOnload(object, attribute, val) { if(window.addEventListener) { window.addEventListener('load', function(){ object[attribute] = val; }, false); } else { window.attachEvent('onload', function(){ object[attribute] = val; }); } } </script> <div id="navbar-iframe-container"></div> <script type="text/javascript" src="https://apis.google.com/js/platform.js"></script> <script type="text/javascript"> gapi.load("gapi.iframes:gapi.iframes.style.bubble", function() { if (gapi.iframes && gapi.iframes.getContext) { gapi.iframes.getContext().openChild({ url: 'https://www.blogger.com/navbar.g?targetBlogID\x3d1383075242687073485\x26blogName\x3dPHYSICS+BLOG+physics-more-difficult-t...\x26publishMode\x3dPUBLISH_MODE_BLOGSPOT\x26navbarType\x3dBLUE\x26layoutType\x3dCLASSIC\x26searchRoot\x3dhttps://xyriztan.blogspot.com/search\x26blogLocale\x3den_US\x26v\x3d2\x26homepageUrl\x3dhttp://xyriztan.blogspot.com/\x26vt\x3d-8230379298686850836', where: document.getElementById("navbar-iframe-container"), id: "navbar-iframe" }); } }); </script>
Tuesday, August 21, 2007
COMPARISON OF A HUMAN EYE TO A CAMERA

this is one of the must-post topics so here it goes...

(Pretty much the same with the website but I thoroughly read it (>_<("') )

HUMAN EYES vs. CAMERA

Human eyes have often been compared to cameras. They are alike in terms of structure, but they have one fundamental difference in functioning mechanism.

The image “http://library.thinkquest.org/28030/media/evocam5.gif” cannot be displayed, because it contains errors.
DIAGRAM From ://library.thinkquest.org/28030/media/evocam5.gif


Function Camera Human Eye
SIMILARITIES
1. opening for light to enter aperture pupil
2. control the amount of light entering camera/eye diaphragm control size of aperture iris muscles control size of pupil
3. refract light glass biconvex lens mainly cornea ;
lens, aqueous & vitreous humor
4. object of light action to form image photosensitive chemicals on film photoreceptors(rods & cones) in retina
5. absorb excessive light to prevent multiple images formation dark internal surface pigmented, dark chloroid
Difference
1. focusing mechanism change distance between lens & film change focal length of lens using ciliary muscles

Death Note

Monday, August 6, 2007
THE RAY METHOD

THE RAY METHOD

I know all you people out there are familiar with this so I didn't include more elaborate things to point out, I'll just post this. ("')(>_<)("')
Images formed by a converging spherical mirror


Characteristics of the Image
a) Distant objectRay diagram for distant objectReal
Inverted
Smaller than object
At F
b) Object beyond CRay diagram for object beyond cReal
Inverted
Smaller
Between C and F
c) Object at CRay diagram for object at CReal
Inverted
Same size as object
At C
d) Object between F and VRay diagram for object between F and VVirtual
Erect
Larger than object
Behind mirror
e) Object at FRay diagram for object at FNo image
Reflected rays
are parallel
Images formed by a diverging spherical mirror
e) Object at FRay diagram for diverging spherical mirrorCharacteristics of the image regardless of object postion
Virtual
Erect
Smaller than object
Behind mirror between F and V

Death Note

THE RAY METHOD

I know all you people out there are familiar with this so I didn't include more elaborate things to point out, I'll just post this. ("')(>_<)("')
Images formed by a converging spherical mirror


Characteristics of the Image
a) Distant objectRay diagram for distant objectReal
Inverted
Smaller than object
At F
b) Object beyond CRay diagram for object beyond cReal
Inverted
Smaller
Between C and F
c) Object at CRay diagram for object at CReal
Inverted
Same size as object
At C
d) Object between F and VRay diagram for object between F and VVirtual
Erect
Larger than object
Behind mirror
e) Object at FRay diagram for object at FNo image
Reflected rays
are parallel
Images formed by a diverging spherical mirror
e) Object at FRay diagram for diverging spherical mirrorCharacteristics of the image regardless of object postion
Virtual
Erect
Smaller than object
Behind mirror between F and V

Death Note

Saturday, August 4, 2007
Fibuh Optiks

Fiber optics

•(optical fibers) are long, thin strands of very pure glass about the diameter of a human hair. They are arranged in bundles called optical cables and used to transmit light signals over long distances.


Parts of a single optical fiber

If you look closely at a single optical fiber, you will see that it has the following parts:

  • Core - Thin glass center of the fiber where the light travels
  • Cladding - Outer optical material surrounding the core that reflects the light back into the core
  • Buffer coating - Plastic coating that protects the fiber from damage and moisture
Hundreds or thousands of these optical fibers are arranged in bundles in optical cables. The bundles are protected by the cable's outer covering, called a jacket.

Optical fibers come in two types:

  • Single-mode fibers
  • Multi-mode fibers

Single-mode fibers have small cores (about 3.5 x 10-4 inches or 9 microns in diameter) and transmit infrared laser light (wavelength = 1,300 to 1,550 nanometers). Multi-mode fibers have larger cores (about 2.5 x 10-3 inches or 62.5 microns in diameter) and transmit infrared light (wavelength = 850 to 1,300 nm) from light-emitting-diodes (LEDs).

Some optical fibers can be made from plastic. These fibers have a large core (0.04 inches or 1 mm diameter) and transmit visible red light (wavelength = 650 nm) from LEDs.

How Does an Optical

Fiber Transmit Light?

Suppose you want to shine a flashlight beam down a long, straight hallway. Just point the beam straight down the hallway -- light travels in straight lines, so it is no problem. What if the hallway has a bend in it? You could place a mirror at the bend to reflect the light beam around the corner. What if the hallway is very winding with multiple bends? You might line the walls with mirrors and angle the beam so that it bounces from side-to-side all along the hallway. This is exactly what happens in an optical fiber.


Diagram of total internal reflection in an optical fiber


THAT'S ALL FOLKS!!!

Death Note

Refraction- The bending of light as it moves from one substance to another.
Ask students for any more examples they can think of where refraction takes place? After students start into different kinds of lenses start with this... Then, start on how lenses, a piece of material which light is able to pass through, are used to refract light. Also, explain that there are different types of lenses.
•Convex
•Concave

Convex - A lens which is thicker in the middle than on the ends.
Concave - A lens which is thinner in the middle than on the ends.


The image “http://physwebdev.physics.uiuc.edu/Van/qa/pictures/1946/889377729__lens.GIF” cannot be displayed, because it contains errors.
A MINI DIAGRAM OF MINE

Way to remember the difference: A concave lens looks like the opening to a cave, therefore you can remember that it curves inward.

Convex Lenses Characteristics:

•Refracts parallel light rays so they come together at a single point. Does anyone know what it is called when the light rays are made to come together?
-Known as convergence.

•Point is known as focal point.
•Distance from center of lens to focal point = focal length.
•The thicker the middle of the lens the shorter the focal length.
•Example of a convex lens is a magnifier.
•Image can be seen without actually looking through the lens. This type of image is known as a real image.
•When held close to objects, inside of its focal length, it produces an image known as a virtual image. To see a virtual image you must look through the lens.

Concave Lenses Characteristics:


•Refracts the rays so they come apart. . Does anyone know what it is called when the light rays are made to come apart from each other?
-Known as divergence.


•Always forms a virtual image.

Death Note

Monday, July 23, 2007
no physics today???

o yah, its the state-of-the-nation address alright... mr. mendoza is absent today(no physics), i wonder if he watched sona??? /pif

Death Note

Wednesday, July 18, 2007
what a test....

44 out of 70 not bad at all, mali pa ako sa test II (wala lng kasing units eh wahahahaha)

Death Note

PROFILE

Xyriz Czar Tan
III - Ptolemy


VOICES WITHIN





MY WILL

WISHES HERE(:

Allies

Ptolemy



Archives

June 2007
July 2007
August 2007


CREDITS

Designer: Kwun Hin(:
Images: Absoluteanime
Image Host: Photobucket