**Official June 2013 SAT II Physics Thread**

<p>For the x y post thing, I said that both x and y have a positive charge because the negative rod reaches equilibrium with the post and then the charge on the post is spread equally over the sphere</p>

<p>Wait, did it say that the post actually touched the sphere? I thought it was just charging by induction</p>

<p>@zhuq1688
Wow…I never thought of that!!! will you please tell me if you get an answer from collegeboard because that really scared me!</p>

<p>@taffyrooster
they never touched</p>

<p>I thought it was charging by induction too but I couldn’t find the right answer in the choices. I would think that the right post (x or y I don’t remember) would be negative and the left would be positive but that wasn’t in the choices…</p>

<p>curves aren’t based on test day score results.</p>

<p>Sorry guys I didn’t to imply that they did. I know they charged through induction.</p>

<p>i guessed on that one, i put that the potential was = o.O</p>

<p>@swagmaster420x
Which one?</p>

<p>what was the answer to that question with a 10V battery, a 2ohm resistor, and a 2uf capacitor?</p>

<p>I said 0, since they were equilbrium. Either that or the product of capacitance and charge</p>

<p>what were some other hard questions? i thought the test was pretty easy</p>

<p>btw for the qusetion with wires of different thicknesses… current is constant, only resistance is different</p>

<p>@gradient time observed from somewhere not moving at the close-to-speed of light speed is longer than the time observed at the close-to-speed of light speed, so it has to be 5/4 or 5/3… the answer is for sure 5/3</p>

<p>Someone should make a question pool…my memory isn’t good enough…please</p>

<p>can we plz discus asnwersz</p>

<p>Ok for the time dilation question, it said that the time for something ( I forgot what it was ) that was moving near the speed of light was T…it asked how the time on earth could be represented. This would be t “initial” …so… t “initial” divided by (3/5) is = to T. That’s the time dilation question. Therefore the answer should be (3/5)T. DILATION means getting larger, meaning that time feels longer when moving near the speed of light. Ergo, the time on earth has to be a fraction of the dilated time, so it clearly can’t be a fraction that is greater than one.</p>

<p>The answer to the charge on capacitor problem was 0??? Why???</p>

<p>What were the choices for what the fundamental frequency depends on?</p>

<p>I put 20 x 10^-5 for that one. I’m pretty sure it was straightforward CV.</p>