The Official October 2012 Sat Subject Test Physics Thread

<p>crap that makes sense. ok i was just being absurdly stupid on that test.</p>

<p>Oh what was the area under the F vs. x graph…? Work? Impulse?</p>

<p>Potential energy i believe? F*x has the dimensions of energy so that’s what i guessed.</p>

<p>@inject @just I said potential energy but I wasn’t sure.</p>

<p>it was the only answer choice that had the dimensions of energy, so i think we’re good.</p>

<p>Idk why I come here. It always makes me so insecure about my answers.</p>

<p>I’m not sure. Do you remember any other questions?</p>

<p><a href=“Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos”>Yahoo | Mail, Weather, Search, Politics, News, Finance, Sports & Videos;

<p>This says the area under a F vs. x graph is work…
<a href=“In a Force vs Distance graph, is work the area underneath?”>In a Force vs Distance graph, is work the area underneath?;

<p>What about, in the last five questions, that one with two solenoids (hoops) and it asked for the direction of the mag field?</p>

<p>F = kx
Fx = kx(x)= kx^2</p>

<p>potential energy of spring: 1/2(kx^2)</p>

<p>so yeah. its potential energy</p>

<p>gah made soooo many dumb mistakes…</p>

<p>@justPhysics</p>

<p>is that the one where there were two bars on top of another and each had current (I) going in opposite directions?</p>

<p>But when you integrate it’s like the same think as multiplying:</p>

<p>Area under V vs. t graph is d = vt. Area under F vs. t graph is impulse = Ft so isn’t the area under a F vs. x graph the work since work = F*d?</p>

<p>what about the question with three pictures and asking for which ones have induced current</p>

<p>@azngeneration21c </p>

<p>No, but what was the answer to that one?</p>

<p>was there a choice that said work and another that said potential energy?</p>

<p>Oh I think that was only the first two, not the one where the square was being rotated counter-clockwise.</p>

<p>I honestly don’t remember seeing potential energy as a choice. But work = potential energy so ***</p>

<p>@justPhysics</p>

<p>im not sure… what did u get?</p>

<p>Wow. I studied mad hard for this test, lots through summer, but I very well might have not got an 800, considering the 60/75 raw score thing. Just annoying considering that I didn’t pick up math 2 book, but still did 800 and bio is a joke</p>

<p>@justPhysics the energy of the thing traveling at c was the last option, because anything at c take infinite energy, not mc^2. Also Fcostheta/h would not be acceleration. the magnitiude of acceleration is constant and therefore a straight line.</p>

<p>What did you guys say for the the one where that negative pointy thing made the shutter things move. I said that the theta decreases and then increases do to the accelerating coulumb force. </p>

<p>Also, did any of you guys know about the double hoop magnetic flux thing. I figured that lenz’s law would mean that B would go to the left, to oppose the current b direction, and somehow the current in the second hoop would go opposite the first one. Can anyone verify this somehow. </p>

<p>Do you guys remember getting 56 for the resonance water thing? Wow and that thing with the star formation was just stupid. Why do they feel a need to expand the material. The physics SAT is hard enough. Damn. Luckily i guessed that quasar thing, because I had never heard of it.</p>

<p>wait what was the answer to that star thing? Wasn’t it black hole. cuz i mean, it’s not a star?</p>