<p>@Hotinpersuit
No way the question underneath beats in quality, its either resonance or pitch, I think he meant that the bottom question was quality.</p>
<p>I put beats, either quality or resonance (don’t remember), pitch. Could someone also explain the one with the car and static shock please.</p>
<p>ya I alredy told you I got them mixed up. I don’t know the right order but resonanace is not one of the three answers</p>
<p>This is what I got for the matching section on sound:</p>
<ol>
<li><p>Caused by 2 waves with slightly diff. frequencies–>**Beats<a href=“Not%20too%20much%20explanation%20needed,%20I%20think”>/b</a></p></li>
<li><p>Determined by fundamental frequency–>**Resonance<a href=“People%20have%20posted%20that%20it’s%20pitch,%20but%20I%20disagree.%20Pitch%20is%20determined%20by%20a%20set%20wavelength.%20%20The%20fundamental%20frequency%20(f%20%22sub%20not%22%20or%20whatever%20the%20term%20is”>/b</a> is used to determine the wavelength of harmonics. For violin players, fundamental frequency would be like the A string, 2 times this would be the 1st harmonic one octave above, etc. The harmonics are caused by resonance. This used to be on AP Physics B FRQs quite a bit; that’s where I learned this, since my teacher spent about 2 weeks on this)</p></li>
<li><p>Difference in the sound of a note played on a guitar compared to a note on piano–>**Quality/Timbre<a href=“Think%20about%20the%20sound%20of%20a%20piano%20and%20a%20guitar%20first.%20%20Then%20think%20of%20why%20they%20sound%20different–a%20piano%20string%20is%20hammered%20while%20a%20guitar%20string%20is%20plucked.%20%20Also,%20I%20have%20seen%20a%20few%20people%20post%20that%20the%20answer%20is%20pitch.%20%20However,%20pitch%20is%20how%20high%20or%20low%20a%20note%20is;%20pitch%20of%20middle%20C%20on%20piano%20is%20the%20same%20for%20every%20instrument%20tuned%20to%20the%20same%20frequency”>/b</a></p></li>
</ol>
<p>I love being a musician.</p>
<p>Now that I think about it, I remember that I put beats, resosnance, and quality. I too am a musician and agree with 314159265.</p>
<p>For the energy efficiency problem they used K instead of J like they do in my book. Would you still do the problem the same way?
Also I agree with Willgo about the x and y magnets. To be honest I would be a little angry if it was just implied that the other ends don’t attract.
Also for, beta particle emission question: nuclear mass stays the same, what was the question and can someone explain this?
students record distance travelled: 10.77 is average velocity / 13.4 m in fifth second (*split). I thought it was pretty clear it was 13.4 v in 5th second because the distance traveled was 13.4 and the time was 1 sec so…
Q = cv = 20x10^6, what was this question? Sorry i don’t have a photographic memory like you people 
Sorry for all the questions</p>
<p>Here’s my reasoning for the uncharged metal ball with the negative rod:</p>
<p>Look. You have a negative rod approaching something with both positive and negative charges. Like a hollow metal sphere, the positive charges will be attracted to X and the negative charges will go away from X (probably to Y). So, I thought that X is positive and Y is negative. For some reason, I think CB likes to sometimes assume that electric potential is always positive (regardless of charge) and sometimes that electric potential can be negative (which can be annoying; PM me if you want me to give you a really in-depth rant about this). Because X and Y are differently charged, choices C and D are wrong, and I think the charges in choices A and B were opposite. E is the only one left and makes sense because the magnitude of the charges on X and Y are equal (so I guess you could say that the electric potential is the same).</p>
<p>
</p>
<p>I disagree. Remember that average velocity is distance traveled over time. The data table explicitly showed that in the third second (t=2 to t=3) that the car traveled 10.77 meters. delta x/delta time is the average velocity, which in this case is 10.77/1 which equals 10.77</p>
<p>Yes 314159265, I had the same reasoning as you did and put E. I remember I saw a similar question on a practice test and it said that the charges move in opposite directions. Also, what did you guys put for the question with the ruler that was nailed on one end and if someone hits the other end, what type of motion would it be? I put harmonic motion.</p>
<p>Intensity and monochromatic blue light was the straight line without a slope. Intensity does not affect the energy of the photons.</p>
<p>a) A person throws an objects in the air, which graphs represents velocity v.s. time</p>
<p>answ: the graph with the positive y-intercept that slopes down</p>
<p>b) Which of the following stays constant for (object)?</p>
<p>answ: acceleration</p>
<p>c) What is not true regarding the beta particle?</p>
<p>answ: Minimum potential energy</p>
<p>For the question with the sloped mirror, the answer was the one that looked the least like the other ones (object height becomes its length and its length becomes its height). You can verify this by turning the page so that the mirror will become vertical and doing the normal procedure</p>
<p>314159265: Was it 10.77 velocity in the the 3rd second or average velocity for the whole time?</p>
<p>Velocity in 3rd second.</p>
<p>Ok then I put the same as you, I just forgot the numbers. What was the other answer people put then 13.4 what in the fifth second?
Also for the object in equilibrium I put I only because it doesn’t have to have 2 in the same direction. If this person’s math is correct here is an example where that isn’t true.
<a href=“Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos”>http://■■■■■■■■■■■■■■■■■/question/index?qid=20080122015032AAerHgd</a></p>
<p>Could someone please explain the question with person in the car and the static shock. Wouldn’t the engine running have some affect on the shock, at least more so than the humidity of the air? What am I missing here?</p>
<p>I just did some googling, apparently increasing humidity decreases static electricity. Can anybody explain why?</p>
<p>ya I put I only two for the same reason</p>
<p>Humidity certainly affects static electricity. Case in point - you shock yourself more on a cold, dry day. My physics teacher explained this, but I can’t remember why.</p>
<p>Damn it…</p>
<p>I did put resonance/quality as well. I know resonance is right. quality was explained by 314123423.
Also I concede that 10.77 m/s was the average velocity and the blue light creates a horizontal line. </p>
<hr>
<h2>Consolidated List ~50/75 Questions </h2>
<p>v/2L is fundamental frequency for string fastened at two ends
Resonance was an answer
For the graph given about a wave:
–period = 0.01s
–amplitude = 4
–wavelength = 6
For the graph given about potential energy versus distance:
–potential energy at x1 = a
–kinetic energy at x1 = b
75) B0 isnt necessary for emf (Confirmed)
beta particle emission question: nuclear mass stays the same
radioactive decay with half lives after 90 days = 8
Telephone messages —> visual images on screen = fiber optic cables (Confirmed)
students record distance travelled: 10.77 is average velocity (Confirmed)
two magnets are next to eachother:
–1st question: either one or both are permanent.
–2nd question: both are permanent (<strong>split)
Q = cv = 20x10^6
for 73) current is same (E) I1 = I2 = I3 (current stays same in series circuit)
for 74) use resistance eqn. R = PL/A answer was r3(thinnest)>r1(medium)>r2(fattest)
for the beginning like numbers 6-8 given graphs:
–relationship between mass and energy = E = mc^2 = straight line (B)
–relationship between freq. and energy = E=hf = straight line (B)
–intensity of monochromatic blue light (Straight horizontal line) (Confirmed)
optics question with converging lens: same size upside down
for 72) f/cos thetha
71) F = 40 N
First few questions:
–1) momentum of II is greater
–2) momentum is same
–3) momentum is same
optics question with plane mirror at an angle: image is virtual and not inverted
Least affects static shock when getting out of car: whether the engine is on (Confirmed)
Pulley with 2 masses of 50 N each and in equilibrium: Force on the rope is 50 N
The efficiency one being 40% (500K and 300K)
B for the field line diagrams w/ two opposite charges
80m for dropping something off a cliff
“II only” for the one with large and small boxes with temperature transfer (Confirmed)
For the 5 diagrams as choices with a satellite orbitting a planet. Mass and Radius varied.
–First problem, asked which had greates grav. force = answer E (m=2M r=R)
–Second problem = E (m=2M r=R)
Linear Expansion problem:Temp raised from 20 to 22 over to 20 to 30. deltaT raised 5x, so L raised 5x, and the answer = 0.015 cm
Rutherford Experiment problem: The size of nucleus was significantly smaller than that of the atom
Elevator problem: I only
Which of these could make the net force 0: I and II only (I got “vector sum=0, and that some could be in the same direction”, but not that they could be the same magnitude)
Work is the only nonvector quantity
Wave generator (deep –> shallow): The eqn that relates it is s1/lam1 = s2/lam2 because freq doesnt change : Answer = velocity of the waves changes (can’t remember values but used that equation to get ans = 3.2)
Which waves can interfere(sound somethign somthing) Answer: I, II, and III
Negatively charged rod and X and Y are ends of a piece of metal: Answer: voltage / net force = 0 (</strong>split)
Area under F vs t curve = impulse
Two different frequencies: beats (Confirmed)
Question underneath that: resonance (Confirmed)
Question underneath that: quality (Confirmed)
Center of mass of the frame: point D</p>
<p>What did you all get for the center of mass…I put D, or the center, lower-most option. Also, for the ruler with a solid attached to it, I can assure you that it is uniform circular motion; in my class, we performed an experiment with that.</p>