Alex's Post, October 1, 2008

Hey everybody! It's Alex :) I've never done a blog before so sorry if this sucks. Anyway today in class we corrected the review and did a sheet on the overhead. I'll start with the review.

Here are my crappy examples of question 1:




Make sure your reflected wavefronts are the same length and distance from each other as the incident wavefronts!









Make an imaginary dot behind the barrier the same distance from the barrier as the original dot. From this dot draw you reflected wave rays.


Question 2) reflected wavelength= 1.6 cm

Question 3) a) n=o.75
b) Shallow Water: wavelength=2.07 cm
Deep Water: wavelength=2.75 cm
c) Angle of incidence= 32 degrees

Question 3 diagram)













Question 4) The wavelength of deep water is equal to 4.5 cm

Vs* lambda d= Vd* lambda s which equals lambda d= Vd* lambda s/Vs: this is the equation I used to find this.

With numbers it would look like:
lambda d= (1 cm/s) * (3 cm)/ (2/3 cm/s)


Question 5) The wavelength of 1.4 m would have the greatest diffraction because the longer the wavelength the greater the diffraction.

Question 6) The frequency of 200 Hz would have the greatest diffraction because the smaller the frequency the longer the wavelength and the longer the wavelength the greater the diffraction.

Question 7) Sorry I cannot draw this!
b) The perpendicular bisector indicates an area of constructive interference.
c) P2 is located on nodal line 2.
d) | PnS1-PnS2|=(n-1/2)*lambda: lambda equals 3 cm
e) 3.5 * 3 cm/ 1 lambda= 10.5 cm

Question 8) a) |PnS1- PnS2|=(n-1/2)*lambda: lambda equals 1.6 cm
b) f= V/ lambda
f= 3.44 Hz

So that is the review.

The over head sheet answers are:

1) The red arrows represent light rays.

2) The angle of incidence for light entering the glass is 60 degrees.

3) The angle of refraction for light entering the glass is 34.5 degrees.

4) The value of the angle of incidence leaving the glass is 34.5 degrees.

5) The value of the angle of refraction for light entering water is 40.5 degrees.

6) I would expect the glass to have a greater index of refraction because it's angle is closer to the normal which means it is denser which means it has a greater index of refraction.

7) n= Sin 60 degrees/ Sin 34.5 degrees= 1.5: index of refraction for glass

8) n= Sin 60 degrees/ Sin 40.5 degrees= 1.3: index of refraction for water

9) The light will travel faster through water.


So that is my post, good luck on the test tomorrow I hope everyone does well. And to everyone who's done a post already you should give yourself a pat on the back, scribing is hard work! I don't know who to pick for scribe, I don't really know how it works so I'll pick the wonderfully smart Katie N.
Bye! See everybody tomorrow :)

This is JUNNEL, not mark. :)

HELLO HELLO HELLO it's Junnel :) the one annnnd only, using Mr. Aquino's account due to some difficulties with my own .HAVE to scribe for today's class. It's okay though, we didn't really do much today anyways.

Firstly, we started off with watching the video that we watch every once in awhile. This time we continued off with learning about "Interference" for today's topic.

Secondly, Ms. Kozoriz gave us a worksheet that we did together in class.

ANSWERS (INTERFERENCE EXERCISES):
NUMERO UNO!

A) Draw the line showing the third nodal line to the left of the perpendicular bisector.

B) It is CONSTRUCTIVE

C) I didn't get this answer, but from what i heard it was either FIVE or TEN.

D) Determine the wavelength

PS1 = 12

PS2 = 9.0

PnS1 - PnS2 = (n-1/2)λ

(12cm)(9cm) = (2 - 1/2)λ

(3/2)(3cm) = (3/2)λ

6/3 = λ

ANSWER: 2cm

E) What is the frequency?

v= 5.0 cm/s

λ=2cm

f= v/λ = 5cm/s /2cm

f = 2.35hz

SECOND QUESTION!

A) What is the wavelength?

22cm - 17.5 cm = 1/2λ

(2/1)4.5cm = 1/2λ(2/1)

9cm = λ

B) What is the speed?

v = fλ

v =(6.5Hz)9cm

v = 58.5 cm/s

LAST QUESTION!

A) I don't know what happened to my picture, it wouldn't upload :(

B) It is DESTRUCTIVE

C) It is on the FOURTH LINE

D) What is the distance?

=6λ(2.2cm/1λ)

=13.2

That's all we pretty much did in class. I guess .. I shall see you guys in class. By the way next scribe is Mr. ANTHONY LY! MUHAHA just kidding :) yeah but your our scribe! DON'T FALL ASLEEP! :P

...

Guess who's the scribe for last friday..yes , you guessed right its me erica, yeayy!

First of all, remember the 4 questions we had for homework last Thursday on page 19 on the blue book? (Title: Waves in Two Dimensions Problems )
We corrected them and here are the answers:

... And also last Friday we watched a video called “Reflection and Refraction”. While watching the video, we were given a sheet, titled “ Physics 11 Waves in Two Dimensions Unit: Reflection and Refraction. Were asked to answer the following questions. The guuureeaat thing about last friday was that we didnt have homework: )

oOYeah, we also have a new student in our class, his name is Aldrin. WELCOME Aldrin ,have a great school year.

......Another thing is that we finished the pharagraph on the study guide booklet:

Diffraction and Interference of Waves

When waves reach a small opening in a barrier, they form circular waves that spread out from the opening. This spreading of waves is called Diffraction. The smaller the waveleght in comparison to the size of the barrie, the less the diffraction. When ther are two opening in a barrier, two sets of circular waves are produced. When the new waves interfere with each other, constructive interference produce large waves, and desctructive interference produces a line of nodes.

Thats pretty much all we did last friday, soo the next scribe will be...innnie minnie miney moe, i choose JUNNEL!, your very welcome, muauuaahhahaa!: )
-ericamaquimot

Wednesday, September 24, 2008

Hi guys! This is arlyn (pronounced: arleen) and i am the scribe of the day. In class we performed an experiment on the bending of light. Incase you weren't in class today i'll explain what you need to do so you can do it in the comforts of your home.

Materials needed to perform this experiment are; a sheet of graph paper, a ruler, marker, water, and a transparent half circle container.

Procedures
1. First you need to draw a horizontal line across the middle of the sheet of graph paper. With a marker draw a verticle line in the centre of the flat and curved side of the semi-cicle container.
2. On the line previously drawn trace the container, marking where the line you drew the container is. Fill the container with around a half or three forths of water and place it in the semi-circle outlined on the sheet.
3. Lets call the flat side of the container side a and the the curved part side b. At eye level with the container on the paper, look through b and align the ruler with the line of side a. Repeat this step five times at different angles
4. Repeat step three but look through side a and align the ruler with side b.

I don't have the lab questions with me right now so i think you should get one as soon as possible. Hopefully my instructions were clear enough for you guys to understand. k bye! =D

I would have picked Mark to be the scribe again but i don't think it's allowed.. so i choose Dearly ! Bwahahaha :P

Tuesday, September 23, 2008

Hey everyone! It's me, Allison, taking Arlyn's place of scribing for today.We started class off by going over Snell's Law for Water Waves, which can be found on page 12 of our Waves in Two Dimensions booklet. After that, we completed the 3rd page of the Guideline to Drawing Problems booklet. In case you missed it, here are the answers:

a) n = Vd / Vs = 40cm/s / 30cm/s = 1.3

b) λdeep = Vdeep / F = 40cm/s / 10.0 Hz = 4cm
λshallow = Vshallow / F = 30 cm/s / 10 Hz = 3cm

c) There are there possible ways to answer this question.

The first way is:
Vd / Vs = sinθi / sinθr
sinθr = (sinθi)(Vs) / Vd
= (sin30°)(30.0cm/s) / (40.0cm/s)
= (0.5)(30) / 40
sinθ = 0.375
θ = 22°

Another way is:
λd / λs = sinθi / sinθr
sinθr = (sinθi)(λs) / λd
= (sin30°)(3cm) / 4cm
= 0.5(3) / 4
sinθr = 0.375
θr = 22°

And the final way:
n = sinθi / sinθr
sinθr = sin30° / 1.3
θr = 22°

Once we finished that, we were assigned two sheets, both labelled Refraction. I'm guessing they are due tomorrow? If not, then Thursday for sure. We were also given a green sheet which had the index of refraction for different substances as a reference.

Yeah, that was pretty much it. Hmn, the scribe for tomorrows class will be Arlyn Guevarra. I'll see all of you guys in class, haha. Later gater! :) - Allison

Waves in 2 D

Hey guys! This is Mark and I am the scribe for today. Today in class, Ms.Kozoriz gave us our "Waves in One Dimension test" back and she corrected the test with us. Here are the answer to the test if any of you guys missed out on it.

1.

2. Amplitude = 1.5cm
wavelength = 4.5cm

3. Transverse wave

4. Longitudinal Wave

5. Compression, Rest Point, Rarefaction, Amplitude, Compression

6. F=λ/T = 10/0.5s = 20Hz

7. 120s/80 = 1.5s

8.

9. F=λ/T = 240/0.30m/s = 800Hz

10. λ=Z/F = 340ms/510Hz = 0.67m

11. 1)B
2)C
3)C
4)A
5)A

12. a)Destructive
b)Constructive
c)Constructive
d)Destructive

13. A standing wave is a result in of two wave trains of the same wavelength, amplitude traveling an opposite direction through the same medium.
No it doesn't stand still

14.


15.

16.




We also watched a video about "waves in two dimensions" which helped us with our previous assignment "waves in two dimensions - assignment 1" we pretty much did a review on what we did last Friday, and if you look at Lorenz's previews post, it explains what we reviewed in class.

OKAY, THAT'S ALL FOR NOW

Next Scribe: Arlyn Guevarra

Note for Ms.Kozoriz
Junnel needs to talk to you

Friday, September 19 , 2008

hi guys...it's me Lorenz....so now you all know that I'm doing the scribe for last Friday.

So, what we did on Friday is we went over the A.Two-Dimensional Waves and the Ripple Tank, B.Wavefronts and Wave Rays, C.Reflection from a Straight Barrier: Wavefronts, D.Reflection from a Straight Barrier: Wave Rays and a little bit of section E.Reflection of Circular Waves from a Straight Barrier from the blue booklet: Two Dimensional Waves.

Wavefront - is a continuous crest and trough.
Wave Ray - is an arrow at right angles to the wavefront.

We also did the Exercises sheet. Here are some examples that we went over through.




Wavefronts are always perpendicular to the waveray.



This an example of a Reflection from a Straight Barrier.



<--Incident waves
Reflected waves-->
The incident waves approaches a straight barrier and then reflected back along its original path.

Angle of Incidence = Angle of Reflection
Angle of Incidence for the wavefront is the angle between the incident wavefront and the barrier.
Angle of Reflection for the wavefront is the angle between the reflected wavefront and the barrier.
Angle of Incidence for the wave ray is the angle between the normal and the incident wave ray.
Angle of Reflection for the wave ray is the angle between the normal and the reflected wave ray.
Normal is the straight line that is perpendicular to the barrier.


Before the end of the class, she gave us the sheet Waves in Two Dimension - Assignment 1 that needs to be hand in on Tuesday, September 23.


I apologize for the late post guys and hopefully i gave you enough information to understand the topic. The next scribe will be mark aquino. So yea, see you all in class and take care.=)

Thursday Sept.18/08

Hi hi! This is Ryan and I will be the scribe for today =). Today in class we started off with our Waves in 1Dimensions Test. Then after the test Ms.Kozoriz handed us our old homework from previous classes.

They were:

• The Job Description (Why is Physics used in this Career)


• Concept-Development Practice Page 25-3 (Wave Superposition)

The next thing that Ms.Kozoriz handed to us was a new booklet entitled "Waves in Two Dimensions," and also an Excercises sheet. We must read pages 3-4 in the booklet. And after she handed that to us she explained that "Wave fronts are always perpendicular to wave rays." And here is a picture I made on paint that she drew on the board. =).

• The Red Square shows that it is perpendicular
• The Grey Dashed Arrow is the Wave Ray
• The Black Lines are the Wave Fronts
• The space inside the Wave Fronts is the Wavelength or Lambda

And that was pretty much it that we did in class. Ahahaha I thought scribing would be harder but it isn't =/ ahaha. Well anyways that is it. OH and I forgot that you need to be bring:

• Protractors
• Rulers

Because we would be making lots of pictures and such. So I will end my scribe here, and next scribe knows who they are so yeah. See you all in class. XD