Saturday, August 4, 2007
Converging Lenses
Steps:
1.draw/choose a point on top of the object and draw 3 incident rays traveling to the lens.The first ray should be perpendicular to the lens,then draw the refracted ray that passes through the focal point.The 2nd ray should be drawn passing through the focal point,then the refracted ray should be parallel to the principal axis. . Draw the third incident ray such that it travels directly to the exact center of the lens.
2. Get the intersection of the refracted image.
Diverging Lenses
Steps:
1.draw/choose a point on top of the object and draw 3 incident rays traveling to the lens.The first ray should be perpendicular to the lens,then draw the refracted ray that passes through the focal point.The 2nd ray should be drawn passing through the focal point,then the refracted ray should be perpendicular to the object. Draw the third incident ray such that it travels directly to the exact center of the lens.
2.Get the intersection of the refracted rays.
flew into your heart at [2:21 AM]
Our eyes and the camera both has a lens. They also use the same type of lens, the converging lens. Those lenses are found in magnifying glasses, they make an image look bigger. This is why you can see the details in something even if it’s on the other side of the room. One thing about lenses is that they can only focus on things that are the same distance away from them. This is why your eyes can focus on things that are close to you or far from you; just not at the same time. Cameras are the same way . you can only focus them on things that are the same distance away.
In the camera, the lens focuses the light onto a piece of film. The film has chemicals in it that basically trap the image on it, making it permanent. Instead of film, your eye uses something called a ’retina. The retina has lots of little tiny things called ’rods’ and ’cones’ all over it. These are basically tiny antennae that tell your brain about the light that hits them. The rods tell your brain whether there is a light in a certain spot or not while the cones tell your brain of what is the color of the light percepted.
There is one spot on the retina, though, that has no antennae at all. This is the spot where the nerve leaves your eye to go to your brain. At this spot, you can’t see anything at all. That spot called your blind spot. This is one of the reasons that you have two eyes: what you can’t see with one eye you can see with the other. Unlike your eyes, cameras have no blind spot, so they only need to have one lens.
flew into your heart at [2:10 AM]
Wednesday, July 4, 2007
hehe... sound waves?
sb ni sir, sound waves can be classified into three, audible waves, infrasonic waves and ultrasonic waves...
audible waves has a normal range of sound wave which is from 20Hz to 20000Hz...
if it is below audible range it is called infrasonic wave..
ultarasonic naman poh kpag above the audible range...
formula for liquids:
v= sqrt of B/P
^B is the bulk modulus of the liquid
^P is the density of the liquid.
formula for solid:
v= sqrt of Y/P
^Y is the Young's modulus material
^P is the density of material
Sound of Speed in General formula:
v= sqrt of elastic property / inertial property *the same as the formula for liquid and solid
formula for gas:
v= (331 m/s) * sqrt of T/273 K
^331 m/s is the speed of the sound at 0 degree celsius
^T is the absolute temperature
nice day... n22to dn! hehe... (kya cnpag mgpost)
=)
sb ni sir, sound waves can be classified into three, audible waves, infrasonic waves and ultrasonic waves...
audible waves has a normal range of sound wave which is from 20Hz to 20000Hz...
if it is below audible range it is called infrasonic wave..
ultarasonic naman poh kpag above the audible range...
formula for liquids:
v= sqrt of B/P
^B is the bulk modulus of the liquid
^P is the density of the liquid.
formula for solid:
v= sqrt of Y/P
^Y is the Young's modulus material
^P is the density of material
Sound of Speed in General formula:
v= sqrt of elastic property / inertial property *the same as the formula for liquid and solid
formula for gas:
v= (331 m/s) * sqrt of T/273 K
^331 m/s is the speed of the sound at 0 degree celsius
^T is the absolute temperature
nice day... n22to dn! hehe... (kya cnpag mgpost)
=)
flew into your heart at [6:10 AM]
Thursday, June 28, 2007
Make a table of x and y components and add algebraically to find the magnitude of resultant components:
Rx= AxBxCx....
Ry= Ay+By+Cy...
After getting the total of the two components, square them then add.
(Rx)2 and (Ry)2
Then get the square root.
flew into your heart at [7:59 AM]
Graphical Method.
In using this method, we should use a scale. So we use graphical method simply because we can illustrate it by using a figure for example.
Steps:
1. Get first the vectors. You Should use a scale say for example 20 miles=1cm.
2. Then after getting it, draw the first vector. Then, connect the tail of the second vector to the head of the first vector then do the same as with the vectors.
3. Label the degree of angle and specify the directions.
4. With the use of formulas, it is now easy for you to get the magnitude and the direction of the vector.
please keep it mind that this method is only the approximate of the actual answer.
eka^-^
flew into your heart at [7:52 AM]
Tuesday, June 19, 2007
YOU MIGHT BE A PHYSICS MAJOR...
if you have no life - and you can PROVE it mathematically.
if you enjoy pain.
if you know vector calculus but you can't remember how to do long division.
if you chuckle whenever anyone says 'centrifugal force.'
if you've actually used every single function on your graphing calculator.
if when you look in a mirror, you see a physics major.
if it is sunny and 70 degrees outside, and you are working on a computer.
if you always do homework on Friday and Saturday nights.
if you know how to integrate a chicken and can take the derivative of water.
if you think in 'math.'
if you've calculated that the World Series actually diverges.
if you hesitate to look at something because you don't want to break down its wave function.
if you have a pet named after a scientist.
if you laugh at jokes about mathematicians.
if the Humane society has you arrested because you actually performed the Schrodinger's Cat experiment.
if you can't remember what's behind the door in the science building which says 'Exit.'
if you have to bring a jacket with you, in the middle of summer, because there's a wind-chill factor in the lab.
if you are completely addicted to PhysLink.com.
if you avoid doing anything because you don't want to contribute to the eventual heat-death of the universe.
if you consider ANY non-science course 'easy.'
if when your professor asks you where your homework is, you claim to have accidentally determined its momentum so precisely, that according to Heisenberg it could be anywhere in the universe.
if the 'fun' center of your brain has deteriorated from lack of use.
if you'll assume that a 'horse' is a 'sphere' in order to make the math easier.
if you understood more than five of these indicators.
if you make a hard copy of this list, and post it on your door.
a physics major?? how i wish.... hahaha... x.x
honestly, sometimes i do not understand the lessons in physics. at first, it was very interesting for me... i thought that, it's not that difficult for us to catch up with the lessons... but day after day its getting more complicated to me and most of my classmates.. they say that this is one of the very difficult subject in 3rd year....
flew into your heart at [6:07 AM]