<p>But when the boy tries to move toward the dock/point, doesn’t their center of mass go forward? And because physics doesn’t allow for that, wouldn’t something have to go backwards o.o?</p>
<p>Kikuhana: Yah, sorry, I don’t remember what the answer choices were but it would have to either be frequency or the medium. If the medium was water, than the frequency would have to change for the velocity to change (v= fwavelength). And lol, I looked up snells law and feel really stupid now. I think your friend is right: sin(X1)/sin(x2) = v1 / v2 . Didn’t realize velocity was involved though ._. But eff that makes sense. </p>
<p>And for the person sled one, imagine running on one of those barrel things at the playground, where if you run forward, the barrel moves backward. So as the person moves forward, he will be pushing the sled backwards, because of friction.</p>
<p>But how about when he STOPS? O.o</p>
<p>Oh and also, do you know the answer to the superconductor/train thing? I put that the train will go more smoothly… but I had no clue T_T.</p>
<p>yes the train moves smoothly because a superconductor has no resistance. the trap answer to that question was “it can run in cold”, and you might be tricked up if you knew metals become superconductors at cold temperatures</p>
<p>yah the superconductor reduces the resistance so yes it makes the train go more smoothly</p>
<p>hey just a quick question…how does the sat physics compare with ap physics B? well at least the mc section of it…i’m only in first year physics but i signed up for the physics b test to do “for fun” 
(-.- i know i’m probably a weirdo)</p>
<p>There was one I, II, III question about the particle nature of light - anyone remember what they put for that one?
And there was another question right under it: I think it was about putting in energy to get electrons out from a metal o.o?</p>
<p>is 5 wrong 800??</p>
<p>^Definitely.</p>
<p>wait kikuhana, what were the questions?
oh the second one about energy to get electrons out of metal…that was like III only i THINK??? OH NO. MORE QUESTIONS IM UNSURE OF</p>
<p>I. Current passed through gas.
II. Something about diffraction pattern.
III. Description of photoelectric effect.</p>
<ol>
<li><p>What proves particle nature of light?
I put I, II, III because I wanted to put just II and III but they didn’t have the choice… I read somewhere that Young’s double-slit helped prove both wave AND particle nature but my friend tells me it’s just III.</p></li>
<li><p>What gets electrons out of stuff/metal?
I put just III but my firend says it’s just I since ionizing gases gets electrons out, too. I dunno if the question asked about getting electrons out of metal or stuff in general though D:.</p></li>
</ol>
<p>did you get G/9?</p>
<p>Was this one of the last questions o.o?</p>
<p>Oh, and did anyone get 30% estimation for error?</p>
<p>I thought Young’s double slit helped with the wave nature of light and so I put down II.</p>
<p>does anybody remember the questions 1 n 2? about potential and kinetical energy? r that were A,B?</p>
<p>I believe so - that’s what I put :P.</p>
<p>And for the other quetions about electrons out of metal, I thought that it might be I and II as well, but I doesn’t refer to the actual photons being shot out from metal and related more to quantum energy and didn’t refer to metals, as you said, and so I think it’s just III.</p>
<p>in graphs about thrown ball what were the graph of time, distance, acceleration?</p>
<p>What about the question in which there were two conducting spheres with equal charges and were seperated by an angle (theta), Afterward a neutral sphere touches one of the spheres and is removed, What happens to the angle between them? </p>
<p>I’m sure i got it wrong. :/</p>
<p>The superconducting questions answer was that the train would require less power to function. This is because of the simple V=IR, and P=IV, so less resistance means less input power and less power disappated. This is why superconductors are used in maglevs and particle accelerators such as CERN - high power output and virtually no resistance.</p>
<p>Also, edifier: both are displaced equally from the vertical line, but the angle between them decreases. The answer was either D or E I think.</p>