What can I use to test the difference between the sounds in different particles it's traveling through?I need .Sound Detector help for a project in...

This would be a great science project. What you will need
is:

two small microphones (you could harvest them from any
number of sources; a trip to your local thrift store is likely to net you discarded
electronics with microphones. It would be best if they were identical, but this is not
absolutely necessary.)

A noisemaker. This could be, for
example, a small speaker that plugs into a
laptop.

Multiplex the two microphones so that they both
feed into a single stereo jack. Make sure that the wire lengths are the same for both
Set up the experiment to that both microphones are in your environment and are separated
by a known distance L.

Create your environment. I would use
some sort of rubber tube where you can place the microphones/speaker inside (isolate
them from external noise), and seal it off to contain the gas. If you use something hard
like plastic or glass, remember that the sound will travel faster along the length of
your environment than it does in the gas
inside.

To make your measurement, simply use an
audio recording software like Audacity and record what happens after you emit a beep
(make it as short as possible, and at a single frequency). You should see two
corresponding peeks on the audio recording. The distance between these two peeks is your
time measurement.

now you know a = L/t, the speed of
sound.

some
tips:

1) don't use hydrogen. You can't get it, and it
explodes. You could use helium instead; it's plentiful and
fun.

2) don't use oxygen. You might be able to get it, but
it can burn violently. use air instead; it's plentiful and lets you breath. Or, nitrogen
if you can find some.

3) Don't rule out liquids or solids.
You can set up a tube filled with water, jello, or even a solid glass
rod.

4) Be prepared to interpret your results. Remember
that there are many pathways for sound to get from from the buzzer to the microphones.
You have to deal with echos, also. Do the math, know what to expect, and use that to
help interpret your results.

5) Set up an audio filter. If
your beep is at a single frequency, you can set up your audio software to exclude
everything but that frequency. This would help you demonstrate your experiment in a
noisy environment, say at the science fair.

6) make your
beep as short as you can.

7) make L long. The two peeks
will blend together if your beep is not short enough or L is too short. If your tube is
coil-able, you can get really long lengths into a small
volume.

8) there are easy ways to get the audio data into
excel. If you look into it, you can make some nice charts. But the audio signal will
probably be sufficient for your needs.

Good
Luck!

An experiment to measure the acceleration due to gravity g of a pendulum is done. The length of threads l/m are 0.35, 0.65, 1.00, 1.45, 1.95 &...

I like to do this a different way, although we get the
same result.

Start with T = 2 * pi *
sqrt(L/g)

Solve for g:  g = (4 * pi^2 *
L)/(T/20)^2

I hope you can read my notation.  The factor of
T/20 is because we are given the period of 20
oscillations.

Substituting our data for L and T, we
get

L           T          
g

0.35      24.1     
9.52

0.65      32.4     
9.78

1.00      40.1     
9.82

1.45      47.5     
10.15

1.95      56.3     
9.71

The value of 10.15 is probably an outlier that we
could discard, but what the hey.  The average value for g
is

g = 9.80 m/s^2, in good agreement with the
textbooks.

Comparing with the previous
response:

His value for g = pi^2 = 9.87.  I think his
answer is different because he simplified, considering only the data for L= 1 and T/20 =
2.

Incidentally, I did all the arithmetic with Excel, the
poor man's mathematical analyser.

What is the mood throughout the short story of "A Christmas Memory"?

Mood, or the emotional effect that a text has, remains
pretty much constant throughout this excellent reminiscence until the end, when the
flashback to the narrator's childhood ends and we are thrust into the present and forced
to see the impact of time on us all.

It is clear that the
prevailing mood of this excellent tale is one of nostalgia - we are thrust back into an
old-fashioned country Christmas from the very first
paragraph:

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Imagine a morning in late November. A coming of
winter morning more than twenty years ago. Consider the kitchen of a spreading old house
in a country town. A great black stove is its main feature; but there is also a big
round tabel and a fireplace with two rocking chairs placed in front of it. Just today
the fireplace commenced its seasonal
roar.

Note how the details of
the fireplace that has just been lit and the coming of winter create an atmosphere of
Christmas with all the accompanying excitement and delight. This is a nostalgic mood
that continues as we look back to how Christmas was and join in the struggle of baking
and posting all of the cakes with the narrator and his
friend.

However, from the one-sentence paragraph, "This is
our last Christmas together", it is clear that life moves on and that time makes such
poignant activity, just a "Christmas Memory" and even results in the death of
Queenie:

A
message saying so merely confirms a piece of news some secret vein had already received,
severing from me an irreplaceable part of myself, letting in loose like a kite on a
broken string.

It appears
that time separates us from both our past and from those that we love best. It is this
shift that moves the mood from one of nostalgia to one of sadness and sombreness as we
recognise the dominion that time has over us as well.

What does that suggest about beauty (or ugliness) as a character trait?

In most Austen novels we see how the characters who are less
important are also described as "plain" or "not as beautiful" as the characters that serve as
ornamental balances in contrast to the strong personality and psychological traits of the main
female character. The word "plain" is about the equivalent of unattractive and is less used as a
term than "not as pretty". In the "plain" characters we also see flat personalities and
unimpressive characteristics. This can help us conclude that Austen assigned physical beauty to
characters who were most passionate such as Sir Walter and less aesthetic importance to
characters that led the story with their strength and balance such as
Anne.

In Pride and Prejudice, for example, we
see how Elizabeth is "not as pretty as Jane", who is ornamental in comparison to Elizabeth's
strength of character and sense of balance. Yet, the sister with the most flat personality, Mary,
is described as "plain".  

Similarly the Dashwood sisters feature
the pretty Marianne in contrast to the more sensible Elinor in Sense and Sensibility.

Conclusively, Austen allows the reader to create a bond
with those characters described as "attractive" to perhaps enhance the romantic element of the
story, and gives us cues as to the character traits of specifically flat characters by describing
them as "plain".

What is a main conflict from Chapters 6-8 in The Outsiders by S.E. Hinton?

To me, the most important conflicts of these three
chapters involve Johnny.  One is between Johnny and another person (his mother) and one
is between Johnny and nature (the fire and its effects).

I
think that the conflict between Johnny and the fire and its effects is the most
important.  It is so important because Johnny is going to end up dying after his
struggle and his struggle and death will have such a huge impact on
Ponyboy.

The conflict between Johnny and his mother is
important for similar reasons.  It emphasizes what a tough life Johnny has had and makes
us (and Ponyboy) sadder when he dies.  It will also help lead to Dallas's
death.

Write as partial fractions . (5x-4)/(x-2)(x+3)

We'll decompose the fraction into elementary irreducible
fractions:

(5x-4)/(x-2)(x+3) = A/(x-2) +
B/(x+3)

We'll calculate LCD of the 2 fractions from the right
side.

The LCD is the same with the denominator from the left
side.

LCD = (x-2)(x+3)

We'll multiply
both sides by (x-2)(x+3) and the expression will become:

(5x-4) =
A(x+3) + B(x-2)

We'll remove the
brackets:

5x - 4 = Ax + 3A + Bx -
2B

We'll combine like terms form the right
side:

5x - 4 = x(A+B) +
(3A-2B)

Comparing we'll get:

5 =
A+B

-4 = 3A-2B

We'll use the symmetric
property:

A+B = 5 (1)

3A-2B = -4
(2)

We'll multiply (1) by 2:

2A+2B = 10
(3)

We'll add (3) to (2):

2A+2B+3A - 2B
= 10-4

We'll eliminate like terms:

5A =
6

We'll divide by 5:

A =
6/5

We'll substitute A in (1):

A+B =
5

6/5 + B = 5

We'll subtract 6/5 both
sides:

B = 5 - 6/5 => B = (25-6)/5 => B =
19/5

The given fraction written as partial fractions
is: (5x-4)/(x-2)(x+3) = 6/5(x-2) + 19/5(x+3), where
6/5(x-2) and
19/5(x+3) are partial
fractions.

In To Kill a Mockingbird, what do the mockingbird, the chiffarobe and Atticus's glasses symbolize?How does Harper Lee use them to develop her...

A mockingbird is an innocent creature that is victimized by
society.  Atticus tells his children that mockingbirds only create beautiful music, and do not
harm anyone, so it is a sin to kill one.  There are at least two mockingbirds in the book.  The
first is Boo Radley, who is discriminated against because he is different.  The second is Tom
Robinson, who is discriminated against by society because of the color of his
skin.

The chiffarobe is a big bulky piece of furniture that has
outlived its usefulness.  It represents society’s prejudices and discriminations.  Mayella asks
Tom to chop it up, as if eliminating society’s restrictions were that easy.  Unfortunately,
racism is not destroyed that easily.

Atticus’s glasses represent the
wisdom that comes with age.  The tale is first and foremost a coming of age story.  As the
children grow, they learn how the world works.  Atticus already knows, but he harbors hope that
he can reverse the trend.  As glasses can come off, Atticus tries to remember that he believes
people are good and society can change.