Delayed Devotion... No I'm not trying to suck up. It just happens to be the title of the song I'm listening to. Google it. ha ha just kidding. I'm a little late with the post, I'm sorry. I wasn't really feeling up to it, even though I said I would do it, mostly because I was watching SNL parody Sarah Palin. ;D
Anyhoo. This scribe post is here to recap what happened since the blog abruptly stopped, so I think that was a Wednesday. On Wednesday, everyone was reviewing for the test the next day using the blue booklet; Waves In Two Dimension. As well as that we were also given review sheets the previous day and reviewed the answers as a class.
The next day was Thursday, and subsequently, we all wrote the test. At the end of class, prior to leaving, we were given the booklet that summarized the next unit, which was SOUND. We're most likely to get thorough on this unit this week.
Finally on Friday, we were given a lab where the objective was to observe the results of making sounds with a ruler on the edge of the table, filling a graduated cylinder with different levels of water and blowing air into it for a sort of windpipe sound and also hitting a "hammer" on a tuning fork. After the class experimented with these items and made different sounds, we were to record our data by answering the questions and hand the paper in.. [but i didn't, tee hee. I will.. I'm just perfecting the paper.]
Then we also had to grab a worksheet CHAPTER 15 Vocab review and fill in the blanks in which we are probably going to go over tomorrow. That's all for today folks...
OH YEAH... next scribe....jaaaayp :D
Showing posts with label waves in 2D. Show all posts
Showing posts with label waves in 2D. Show all posts
Sunday, October 5, 2008
Monday, September 29, 2008
Mwahaha! INTRODUCING THE NEW Super Ultra Mega Amazing Blog Post Spectacular as posted by Me!
Haha i just got back from work not too long ago, so naturally I was tired.....
BUT NOW HERE I AM FULLY ENERGIZED AFTER SOME DELICIOUS LIQUID CAFFEINE AND A WHOLE BUNCH OF ENERGY BARS READY TO BLOG!!!! LET'S GET 'ER DONE!!
So basically on Friday we went over something from a while back... That few pages of fill in the blank-y type stuff XD The Chapter 14 Study guide if that helps you at all? Anyways heres how the blanks got filled:
REFLECTION OF WAVES:
The direction of waves moving in two or three dimensions is shown by RAY diagrams. The ray that reaches a barrier is called the INCIDENT ray. The ray that moves back from the barrier is called the REFLECTED ray. The direction of the barrier is shown by a line drawn at a(n) RIGHT ANGLE to the barrier. This line is called the NORMAL. The angle between the INCIDENT ray and the NORMAL is called the angle of incidence. The angle between the REFLECTED ray and the NORMAL is called the angle of reflection. The law of REFLECTION states that the angle of incidence equals the angle of reflection.
REFRACTION OF WAVES:
In water waves, the velocity is SLOWER in shallower water. If the incident ray is parallel to the normal, there is a change in the velocity and WAVELENGTH of the wave. If the incident ray is not parallel to the normal, there is a change in velocity, wavelength, and DIRECTION of the wave. The change in DIRECTION of a wave at the boundary between two media is called refraction.
BUT NOW HERE I AM FULLY ENERGIZED AFTER SOME DELICIOUS LIQUID CAFFEINE AND A WHOLE BUNCH OF ENERGY BARS READY TO BLOG!!!! LET'S GET 'ER DONE!!
So basically on Friday we went over something from a while back... That few pages of fill in the blank-y type stuff XD The Chapter 14 Study guide if that helps you at all? Anyways heres how the blanks got filled:
REFLECTION OF WAVES:
The direction of waves moving in two or three dimensions is shown by RAY diagrams. The ray that reaches a barrier is called the INCIDENT ray. The ray that moves back from the barrier is called the REFLECTED ray. The direction of the barrier is shown by a line drawn at a(n) RIGHT ANGLE to the barrier. This line is called the NORMAL. The angle between the INCIDENT ray and the NORMAL is called the angle of incidence. The angle between the REFLECTED ray and the NORMAL is called the angle of reflection. The law of REFLECTION states that the angle of incidence equals the angle of reflection.
REFRACTION OF WAVES:
In water waves, the velocity is SLOWER in shallower water. If the incident ray is parallel to the normal, there is a change in the velocity and WAVELENGTH of the wave. If the incident ray is not parallel to the normal, there is a change in velocity, wavelength, and DIRECTION of the wave. The change in DIRECTION of a wave at the boundary between two media is called refraction.
As for the last par t about
DIFFRACTION AND INTERFERENCE OF WAVES... i only have the answers to the blanks which are: circular, diffraction, wavelength, less, resulting, constructive, destructive
And then TODAY in class we watched a quick video talking about what we were about to do which waaaaaaas.... read through pages 13 -18 as a class in our super special awesome "Grade 11 Physics: Waves in Two Dimensions" booklet/study guide thang XD ( even though i didn't aget a chance to read D= ) Covering such lovely topics as :
DIFFRACTION AROUND A SHARP BARRIER: VARYING WAVELENGTH
DIFFRACTION THROUGH AN OPENING: VARYING SIZE OF OPENING
DIFFRACTION AND INTERFERENCE OF WAVES... i only have the answers to the blanks which are: circular, diffraction, wavelength, less, resulting, constructive, destructive
And then TODAY in class we watched a quick video talking about what we were about to do which waaaaaaas.... read through pages 13 -18 as a class in our super special awesome "Grade 11 Physics: Waves in Two Dimensions" booklet/study guide thang XD ( even though i didn't aget a chance to read D= ) Covering such lovely topics as :
DIFFRACTION AROUND A SHARP BARRIER: VARYING WAVELENGTH
DIFFRACTION THROUGH AN OPENING: VARYING SIZE OF OPENING
DIFFRACTION THROUGH AN OPENING: VARYING WAVELENGTHS
CONSTRUCTIVE AND DESTRUCTIVE INTERFERENCE IN TWO DIMENSIONS
NODAL LINES AND THE INTERFERENCE PATTERN
MATHEMATICAL ANALYSIS OF A TWO POINT SOURCE INTERFERENCE PATTERN
AND MANY MANY MANY MORE.... reading this information and learning it will definitely get you 100% on the upcoming test ( though results may vary.) That last bit was a bit of a giant contradiciton, but lets just keep the super physics blog rolling shall we?
CONSTRUCTIVE AND DESTRUCTIVE INTERFERENCE IN TWO DIMENSIONS
NODAL LINES AND THE INTERFERENCE PATTERN
MATHEMATICAL ANALYSIS OF A TWO POINT SOURCE INTERFERENCE PATTERN
AND MANY MANY MANY MORE.... reading this information and learning it will definitely get you 100% on the upcoming test ( though results may vary.) That last bit was a bit of a giant contradiciton, but lets just keep the super physics blog rolling shall we?
The main point of varying wavelengths when it came to sharp barriers was this....
BIGGER WAVELENGTH + SHARP BARRIER = MORE DIFFRACTED (BENT)
Cant put it much more simply than that you guys.
The main point for us to learn out of diffraction through an opening: varying size of opening was fairly simple too....
SMALL OPENING + WAVE = MORE DIFFRACTION (BENDING OF WAVE)
BIG OPENING + WAVE = LESS DIFFRACTION
Once again in Diffraction through an opening, this time the size of wavelngth being the variant factor.... the lesson is simple again, borrowed from our sharp barrier equation i dispalyed earlier:
BIGGER WAVELENGTH + OPENING = MORE DIFFRACTED (BENT), In order for any significant diffraction to be noticed, the ration wavelngth/size of opening should be about (or greater than) 1.
BIGGER WAVELENGTH + OPENING = MORE DIFFRACTED (BENT), In order for any significant diffraction to be noticed, the ration wavelngth/size of opening should be about (or greater than) 1.
Next we delved into the delightful ( though not as complicated as it appears) world of INTERFERENCE IN 2D!!!
So my badly scanned diagram shows that cosntructive interference can occur between two crests (represented by solid lines) and two troughs (represented by dotted lines). These produce antinodal areas. If you were to look at it from above... the double troughs would be blinding and the crests would be mad dark.... pretty much. Nodal lines are formed where crests and troughs intertwine to form nodes.
Each side of either of the perpindicular bisector of the distance between the two sources has symmetrical nodal/antinodal lines like so:
After this we learned about how we can determine the wavelngth of a wave in 2D using any point on a nodal line and its distance to the vibrating sources via the formula P1S1-P1S2= (n-1/2) wavelength. An example coyuld be that your point was 12 cm away from source one and 6 cm away from source 2. It is located on the 2nd nodal line.
Your equation would work out like this .... 12cm - 6cm = (2-1/2) wavelength
6cm= 1.5 (wavelength)
wavelength = 4cm
Hopefully that makes sense to you guys and sorry about all hte delay on this and what not haha.. as you can tell througout this post I became deadly tired and am now off to a nice rest in a warm comfy bed to prepare for tomorrows wonderful school day. Thank you again to Mrs. K who let me do this thang... I appreciate more than I can say. I truly do. Oooo next scribe.... Sorry bout this but I'm gunna have to pick the_bdl... Please don't hate me :p anyways bye for now fellow physics lovers!
Thursday, September 25, 2008
September 25, 2008
Hey-o everyone!
Okay, here I am listening to tunes and procrastinating on my English project, all the while wondering what to write in this blog post... Sorry I can't compare to the awesome blogposts already made, I will try not to fail you all!
How about summarizing what we did today? Well, we didn't do much actually. We watched a video on the smartboard that was quite entertaining and informative. We also had to complete a worksheet while watching said video. The worksheet was pretty straightforward since the answers were easily derived from the video. (Don't worry, don't worry, I'll post the worksheet with the answers in a bit...)
The video was mainly about the reflection of light through/off of different mediums. I'd come up with some analogies for the concepts but I wouldn't be able to do the video justice. Gah! I wish I could just find the darned video.
Now here is the worksheet. I apologize for my horrid penmanship and diagrams (oh and my scanning isn't very good but oh well!) D: !!
1) Anywhoots, first we learned how to find the shortest distance light would travel between two points. This is done by drawing a B-prime (an imaginary point beyond the barrier, mirroring the actual point) and connecting it to point A. The point where point B-prime crosses the barrier is the point where point A and point B should meet, thus resulting in the shortest distance to travel. The same applies for question 2.
2) Read my lengthy paragraph above.
3) This is relatively straightfoward. We've been repeating this concept for the past... week? So yeah! The angle of incident = the angle of reflection.
4) Okay, we can compare this to a page in a book because the book's surface is rough, not smooth. If it was smooth, the light rays would reflect much like light would off of a mirror, thus we'd only be able to see the contents of the book at (a) certain angle(s). The rough surface allows the rays to be reflected at different angles which allows us to view the page from any angle. (Hopefully I explained this well enough!)
5) This is similar to the first and second question~!
Okay, since the answers for the rest of the worksheet are easily explained through the context in which it is found, I feel that I don't need to explain anymore. (Plus, I need to get crackin' on my English project D: )
All in all, the video provided new viewpoints for the concepts we are learning, making it easier to understand. I learned and relearned a couple of things. (I mean come on! I had no idea a polar bear is black with white fur :O who'da known? Hahaha!)
Alas, after the video, we corrected the worksheet and attempted to correct a previous assignment... "Refraction - Light." We only got two questions corrected so I shall leave that entirely up to the next scribe... Which just so happens to be...
Okay, here I am listening to tunes and procrastinating on my English project, all the while wondering what to write in this blog post... Sorry I can't compare to the awesome blogposts already made, I will try not to fail you all!
How about summarizing what we did today? Well, we didn't do much actually. We watched a video on the smartboard that was quite entertaining and informative. We also had to complete a worksheet while watching said video. The worksheet was pretty straightforward since the answers were easily derived from the video. (Don't worry, don't worry, I'll post the worksheet with the answers in a bit...)
The video was mainly about the reflection of light through/off of different mediums. I'd come up with some analogies for the concepts but I wouldn't be able to do the video justice. Gah! I wish I could just find the darned video.
Now here is the worksheet. I apologize for my horrid penmanship and diagrams (oh and my scanning isn't very good but oh well!) D: !!
1) Anywhoots, first we learned how to find the shortest distance light would travel between two points. This is done by drawing a B-prime (an imaginary point beyond the barrier, mirroring the actual point) and connecting it to point A. The point where point B-prime crosses the barrier is the point where point A and point B should meet, thus resulting in the shortest distance to travel. The same applies for question 2.
2) Read my lengthy paragraph above.
3) This is relatively straightfoward. We've been repeating this concept for the past... week? So yeah! The angle of incident = the angle of reflection.
4) Okay, we can compare this to a page in a book because the book's surface is rough, not smooth. If it was smooth, the light rays would reflect much like light would off of a mirror, thus we'd only be able to see the contents of the book at (a) certain angle(s). The rough surface allows the rays to be reflected at different angles which allows us to view the page from any angle. (Hopefully I explained this well enough!)
5) This is similar to the first and second question~!
Okay, since the answers for the rest of the worksheet are easily explained through the context in which it is found, I feel that I don't need to explain anymore. (Plus, I need to get crackin' on my English project D: )
All in all, the video provided new viewpoints for the concepts we are learning, making it easier to understand. I learned and relearned a couple of things. (I mean come on! I had no idea a polar bear is black with white fur :O who'da known? Hahaha!)
Alas, after the video, we corrected the worksheet and attempted to correct a previous assignment... "Refraction - Light." We only got two questions corrected so I shall leave that entirely up to the next scribe... Which just so happens to be...
Super Captain Awesome of Extreme Fantasticness!
(C'man, a pseudonym like that should've drawn attention LONG ago!)
(C'man, a pseudonym like that should've drawn attention LONG ago!)
adieu~ ♥!
Wednesday, September 24, 2008
Wednesday September 24, 2008
Hey! Hey! Hey! Everybody! I hope you had a happy Wednesday!
Today in physics we did a lab and it was supposed to further your understanding of how light waves can BEND! So if you weren’t in class today (shame on you), you can probably read the rest of this post and do the little experiment at home. ;)
What you need: A ruler, a sheet of graph paper, a semi-circle dish thing, a marker, water
The Steps: (hopefully I remember right...)
Step 1: With your pencil, draw a line dividing the paper in half.
Step 2: Trace the outline of the semi-circle dish and make sure the flat side of the dish is on the line you just drew.
Step 3: With a marker draw two vertical lines on the side of the dish; one line in the middle of the flat side and one on the middle of the curved side.
Step 4: Place the dish back on the paper in the outline you drew of it and mark where the vertical lines are on the dish on the paper.
Step 5: Fill the dish about halfway with water.
Step 6: Bend down so your eyes are level with the dish full of water. Look for the vertical line you made and with your ruler draw a line in the direction of the mark. Do this four or five times, then repeat on the other side...
...Then fill out the Lab Worksheet... that I’m sure is worth marks...
So basically the gist of this activity was for you to analyze how the light bends and I’ll give you a hint if you’re stuck trying to analyze the bend of the light waves: one side of the dish refracted the light more than the other. ;) (I think... ha ha)
Class was fun today even though I probably screwed this activity up XD
The next scribe is miruiz.
Today in physics we did a lab and it was supposed to further your understanding of how light waves can BEND! So if you weren’t in class today (shame on you), you can probably read the rest of this post and do the little experiment at home. ;)
What you need: A ruler, a sheet of graph paper, a semi-circle dish thing, a marker, water
The Steps: (hopefully I remember right...)
Step 1: With your pencil, draw a line dividing the paper in half.
Step 2: Trace the outline of the semi-circle dish and make sure the flat side of the dish is on the line you just drew.
Step 3: With a marker draw two vertical lines on the side of the dish; one line in the middle of the flat side and one on the middle of the curved side.
Step 4: Place the dish back on the paper in the outline you drew of it and mark where the vertical lines are on the dish on the paper.
Step 5: Fill the dish about halfway with water.
Step 6: Bend down so your eyes are level with the dish full of water. Look for the vertical line you made and with your ruler draw a line in the direction of the mark. Do this four or five times, then repeat on the other side...
...Then fill out the Lab Worksheet... that I’m sure is worth marks...
So basically the gist of this activity was for you to analyze how the light bends and I’ll give you a hint if you’re stuck trying to analyze the bend of the light waves: one side of the dish refracted the light more than the other. ;) (I think... ha ha)
Class was fun today even though I probably screwed this activity up XD
The next scribe is miruiz.
I was supposed to be the scribe Monday, but I was not here, so I will scribe for both Monday and Tuesday today.
We watched a movie and received a couple of worksheets. We learned about Snell's Law for water waves, which allows us to calulate the angles, speeds and wavelengths associated with refraction. The equation was sinθi/sinθr = λi/λr = inr , where the symbols "i" and "r" refer to the incident wavefronts and rays and the refractive wavefronts and rays respectively. The ratio is always constant and this constant is referred to as the index of refraction.
Remember, when water waves move from one depth to another, the frequency of the waves does not change, but the speed and wavelength does. We use vdeep/vshallow = λdeep/λshallow to determine the speeds and the wavelengths. When a wave moves from deep water to shallow water, the speed and wavelength decreases while the wave ray is refracted towards the normal; when a wave moves from shallow water to deep water, the speed and wavelength increases while the wave ray is refracted away from the normal.
~Katherine
We watched a movie and received a couple of worksheets. We learned about Snell's Law for water waves, which allows us to calulate the angles, speeds and wavelengths associated with refraction. The equation was sinθi/sinθr = λi/λr = inr , where the symbols "i" and "r" refer to the incident wavefronts and rays and the refractive wavefronts and rays respectively. The ratio is always constant and this constant is referred to as the index of refraction.
Remember, when water waves move from one depth to another, the frequency of the waves does not change, but the speed and wavelength does. We use vdeep/vshallow = λdeep/λshallow to determine the speeds and the wavelengths. When a wave moves from deep water to shallow water, the speed and wavelength decreases while the wave ray is refracted towards the normal; when a wave moves from shallow water to deep water, the speed and wavelength increases while the wave ray is refracted away from the normal.
~Katherine
Sunday, September 21, 2008
Thursday, September 18, 2008
.:. WAVES IN TWO DIMENSIONS introoo .:.
Hello everyone- Wazzup? [or if you prefer...what's going DOWN, pardon the random wordplay. I'm really bored.] :D I'm scribe today... pretty short notice really. But I'm coping. **sigh** just kidding though. I'm not really that burdened, "weblogging" isn't so baaaaaad. (bah. I have now transformed into a sheep. bah.) Anyhow, not to derail everyone from the TRAIN OF THOUGHT, here's my little abridged version of what happened in our very dynamic physics class. I'm being sincere. The class is dynamic.. you just get a sarcastic tone because this is text. No joke. The class is 'awesometown'.
After recently recovering from our first nerve-wracking test [which was not dreadful,] we started on a new subunit... of the unit which is: WAVES IN TWO DIMENSIONS. For those who took initiative and started looking at the blue booklet last night, the concepts were pretty easy to grasp. As for those who didn't? Well, not much difference there, we read sections C to F aloud after of course doing an exercise sheet that involved the concepts of section B mainly, allowing me to segue into...
OUTLINED POINTS IN B: WAVEFRONTS AND WAVE RAYS
- Initially, as an example, it is mentioned that waves may occur in different SHAPES and SiZeS. ex. Matter touching the surface of water creating a rippling effect like so:
- WAVEFRONT: A continuous crest or trough.
- WAVE RAY: lines that represent the transmission [direction of travel of a wavefront]
- NOTE: Wavefronts are always perpendicular to wave rays. **
In case you missed the answers to the sheet, here they are [including some notes taken]:
FRONT and BACK:
Sorry if the handwriting is illegible.
REMINDER: Answering these on the SmartBoard today, the common mistake was not putting arrows on the wave rays since they indicate direction.
After that, we read the next few sections in the blue notebooks...
C & D: REFLECTION FROM A STRAIGHT BARRIER: WAVEFRONTS and WAVE RAYS
Straight waves travel towards a barrier and is reflected back along it's original path, only if approaching the barrier on a right angle. If incident waves approach the barrier on an angle, the rays are reflected on an angle as well. The angles involved is the angle of incidence and the angle of reflection. These angles correspond to each other, and are equal to each other.
[θi = θr ].Using wave rays, the main difference is that the angles of incidence and reflection are measured relative to a NORMAL.
NORMAL: straight line perpendicular to the barrier and is usually represented by a dashed line.
As for the last section we ended on today, I'm still trying to grasp the idea, so I don't think I can explain it yet. But the main thing was acting as if there was a virtual image of a circular wave on the other side of the barrier. From what I saw from the diagram, as soon as the circular wave makes contact with the barrier, the end seems to flatten and make corners, and result in a crescent shape. This crescent shape is made as if another circular wave was pushing it through the barrier, as shown in the diagram in the booklet.
There you have it, my lengthy and probably really tediously boring scribe post. There won't be a class tomorrow due to the pep rally. But the next randomly selected scriber is...Not Paul May the force of the blog be with you.
and finally... DON'T FORGET Assignment one on this subunit is due...TOMORROW? or Monday, I'm not quite sure, since the pep rally will be taking over our class time. Until then, I'm dunzo. ;)
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