<p>If you look at old AP Physics B FRQs, there are problems asking you to determine the fundamental frequency and use that to determine the 1st, 2nd, 3rd, etc. resonances/harmonics.</p>
<p>@314159265: That’s what I put too. I’m pretty sure a neutrino is emitted in beta decay.</p>
<p>If ‘atom number’ was one of the answer choices, that pretty much seals the deal. Beta emissions convert one neutron to a proton.</p>
<p>Israelexwired: That is true but why would it effect the momentum? Momentum is mass x velocity not atomic number x velocity.</p>
<p>I don’t recall it saying anything about momentum… It asked what is one thing we know happened for sure in the emission.</p>
<p>^ no the question asked for why is momentum is not conserved when comparing the P of electron and P of the atom after decay</p>
<p>When neutron is converted to proton (thus atom number is changed) an electron and a neutrino is also formed. so atomic number change alone CANNOT explain the loss in momentum. </p>
<p>Momentum is ALWAYS conserved in an isolated system. The loss of momentum has to go somewhere, which is the neutrino in this case.</p>
<p>@314159, aka Pi (nice name), I agree with you 100%; I was actually arguing earlier about exactly what you said. To be precise, it is an electron-antineutrino, which is, essentially, an anti-electron (to conserve charge); you can think of it as antimatter. Anyway, it has a mass comparable to that of an electron, and flies off in a different direction, with a momentum, mv. The only two particles moving in this reactio are the electron and the antineutrino, hence, the only thing that could contribute to the change in momentum is the electron-antoneutrino.</p>
<p>That makes sense. I wish that my book had mentioned something about this neutrino.</p>
<p>so about how many do you guys think I can miss to get a 800 on this test, considering the unusual difficulty of the test this time.</p>
<p>By the way, I got a 5 on physics C last year. and took this test w/o much preparation. but I guess I should of brushed up on my memory . .</p>
<p>Any guesses as to what a skip-9, miss-1 or 2 might be? ): Yeah, I should’ve studied … blah.</p>
<p>Hey guys, was the test too easy or am I the only one who feels this way?</p>
<p>I’m pretty sure that would be an 800 coupdefoudre, at least on all of the curves I’ve seen.</p>
<p>@ Pepper ; … Wow. I think I might love you right now. <333 If I skipped nine, how many can I miss while still maintaining a 780-800? :]</p>
<p>Man, you guys leave so few blank. I left 23 blank, but I was at a real disadvantage for this test since I took regular physics (didn’t even know several terms that appeared). I think I got most of the answers I put right going by those consolidated answers and how I felt when actually taking the test. I hope I get a 700+, hopefully a 740.</p>
<p>I’m still leaning towards pitch for the frequency question. Maybe if they had asked about a certain frequency producing larger amplitudes, or a hum, it would have been resonance, but they were asking about what changes the pitch and frequency was the definitive answer. For the speed around the merry-go-round I got pi/2 and I vaguely remember a question concerning the change in kinetic energy of a 5 kg object subjected to some force, my answer was 60J?</p>
<p>Depending on the curve I’d say you could miss from 2-6. The curves I’ve seen have around 63/75 as the lowest 800, but I saw someone said that collegeboard said 59/75 was an 800.</p>
<p>The question about the two charges being moved to double a distance the resulting force of attraction was 1 x 10^4 (originally 4e4). There was a circuit question that was practically identical to one of them in the Blue Book- the one with multiple switches, asking for the greatest current-the answer was I and III because they added up to the least resistance.</p>
<p>Gotta catch 'em all.</p>
<hr>
<h2>Consolidated List 66/75 Questions</h2>
<p>v/2L is fundamental frequency for string fastened at two ends
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
the merry go-around is spinning at the speed of 1/2 pi
75) B0 isnt necessary for emf (Confirmed)
the centripetal force decreased by a factor of 4 (F/4)
acceleration (mass?) of the pushed object is 5x 10^6
beta particle emission question: nuclear mass stays the same
the constant force applied on the 5 kg object was 30 N
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
change in kinetic energy of the object is F * d = 60 J
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 (twist page and deal with it as a normal mirror question)
The resulting force of attraction between the two moved is 1 x 10^4 (originally 4e4)
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
Waves interfere with each other and get diffracted at the two slits.
Switched I and III add up to the least resistance, thus the greatest current
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
F/4 for electrostatic force or something like that
pi/2 for person on merrygoround with radius 3 moving 5 rev /s
Center of mass of the frame: point D
Graph of ax + b is linear with a positive slope and y-intercept
The range of the perimeter of the rectangle where the sides were known to a ±.1 value was a range 13.6 to 14.4
A person throws an objects in the air, which graphs represents velocity v.s. time
–answ: the graph with the positive y-intercept that slopes down
Which of the following stays constant for (object)?
–answ: acceleration
What is not true regarding the beta particle?
–answ: Minimum potential energy
A ruler attached to table undergoes simple harmonic motion
An atom emits a beta particle –> another particle must also be emitted</p>
<p>So here are the answers to some question I don’t think we have listed yet:</p>
<p>*The question about the range of the perimeter of the rectangle where the sides were known to a ±.1 value, it was a range of some number to 14.4 (choice A). </p>
<p>*The acceleration of a ball thrown up and a ball released from rest was the same.</p>
<p>*Circuit question that was practically identical to one of them in the Blue Book- the one with multiple switches, asking for the greatest current-the answer was I and III because they added up to the least resistance.</p>
<p>*Question concerning the change in kinetic energy of a 5 kg object subjected to some force, my answer was 60J?</p>
<p>-For the pitch question, I don’t understand how it could be resonance; can someone please explain?</p>
<p>one thing you forgot to catch, Israelexwired. something like, both the two paths result in the same internal change. that one and…wasn’t there one question asking about the magnitude of the frictional force ? anyone?</p>