Hi guys, it's Suzette. Today, we corrected worksheets.

1. Information in Kinematics Graphs
2. Acceleration Motion I
3. Simple Vectors

Answers: Information in Kinematics Graphs



Answers: Accelerated Motion I

1. a. 15 m/s
b. 18.75 m
2. a. 200 m/s
b. 912.5 m
3. a. 1.5 m/s/s
b. 120 m
4. 250 m
5. 11 m/s/s


Answers: Simple Vectors

1. distance - s
mass - s
time - s
area - s
force - v
displacement - v
velocity - v
acceleration - v

2.


3. a. d= 800 m
b. d= 583
angle = 50 degrees

4. a. f = 200 N
b. f = 0 N
c. f = 1414 N


Then after correcting all those sheets, we did an exercise from the book.

Problem - p. 82 -83, # 1, 5, 8, 10, 11, 16

answers:
1. a = 8.0 m/s/s
5. v2 = 33 m/s
8. a. v2 = 607 m/s
b. N = a. 1.83
10. d = 920 m
11. d = 1700 m
16. v2 = 7 m/s

NEXT SCRIBE IS KIMBERLY!

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Hello guys, it's suzette!

I'm gonna make this short. Today, we just talked about the "Experiment and Modes of Representation". It can be found in the green booklet. This topic is about the different ways in which the relationship between two variables can be illustrated or represented--it includes the numeric, graphical, visual, and symbolic forms.

The Visual Mode

Ex. Adding weights to spring causes it to stretch. The more weight is added, the more it will stretch. Therefore, it is a qualitative observation--what we see is what we get.

The Numerical Mode

In the numerical mode of representation, to be able to collect data, we must define the properties of the object (s) we are measuring and use measurements. Then, the data can be examined to determine the exact relationship.

The relationship can be determined by the two variables:
1. Independent - variable that the experimenter changes in an experiment.
2. Dependent - variable that changes is response to changes in the independent.

The Graphical Mode

The graphical mode is a mathematical picture of the relationship and is a graph of the data. In this mode, the independent variable is placed on the y-axis (horizontal line) of a graph. On the other hand, the dependent variable is place on the x-axis (vertical line). When you have data, you just plot them on the graph and draw a line, joining the points together. Usually, when a graph is formed, it illustrates a linear or direct relationship between the x and y-axis on the graph.

The Symbolic Mode

The symbolic mode represents the relationship as an algebraic formula. The equation of a straight line is y=mx+b. The "m" represents the slope of the line. "B" represents the y-intercept.

For more information, see green booklet pages 8-10.

MOREOVER...

Today, we also did lab. It's just measuring jar lids (measuring diameter and the circumference). Then when enough data is gathered, we're supposed to create a graph to show the relationship between the diameter and the circumference of the lids. Then we just answer the questions written on the sheet. All the information are basically on the sheet so yeah....

It's due tomorrow!

and that is all....

I apologize for lack of information. =)

the next scribe is REBECCA

Sound Stuff

Hello guys! Suzette here, scribing... duhh? Well anyway, today, what we did was go over the test that we wrote last week: Waves in Two Dimensions. I hope you guys are satisfied with your mark 'cause I am, haha. Then after that we went over the yellow booklet and learned more about sound waves... o.o

Here are some facts according to the booklet:

Natural Frequencies and Resonance

Natural Frequency is when an object is allowed to vibrate freely at a specific frequency.

- depends on the size, shape, and composition of the object.

Resonance is the condition in which force is applied to an oscillator at the point of maximum amplitude.

- is a matter of one object "getting in tune" with another object.

The Fundamental Frequency

* A standing wave can only be created in a medium of fixed length at certain frequencies. This wave can exist only at a resonant or natural frequency.

Vibrating objects that have only a single resonant frequency:
- tuning fork
- pendulum
- mass bouncing on a spring

Vibrating objects that have many resonant frequencies:
- rope
- stretched spring
- air in an air column (used in musical instruments)

Fundamental Frequency, f_o is the lowest frequency at which a system vibrates freely (standing waves).

Harmonics - the resonant frequencies of standing waves.

Fundamental frequency = first harmonic

Beats and Beat Frequency

So, what happens when sound waves have slightly different frequencies?

Well....

Let say you have two tuning forks with the frequency of 440 and 438. When you strike these forks, it creates a sound that rises and falls periodically so that it is faint, then loud, then faint again, then loud again, and you get the idea. These vibrations in loudness are known as beats. They are produced by the interference of sound waves with slightly different frequencies.

Beat frequency
- is the number of times that the loudness rises and falls every second.
- is the difference between two sound frequencies.
- based on the tuning forks above: 438 Hz - 440 Hz = 2 Hz
- 2 Hz is the beat frequency.

And that is all about the yellow booklet...

Moving on....

The next thing we did was watch a video about Beats of Sounds (it's the teacher guy who draws awesome straight lines) =)

The video is basically about you know, sounds.

The only thing I remembered is, when you have a water wave and then you add another wave, it produces NOTHING. And it's the same thing for the sound waves, they produce basically nothing. <<<<---- err... this, I'm not really sure. The video is so interesting I didn't even bother to write anything about it. However, if you know or have something to say, just say it so I can, maybe, fix it.

OKay, in addition...

the last thing we did was work on the Vocabulary Review sheet.

The End.

P.S. Sorry for the lack of effort (no illustrations at all).

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The NEXT SCRIBE is LARLYN!