June 2009 - Physics

<p>thats wat i put</p>

<p>I think I did ok; don’t wanna keep my hopes up :)</p>

<p>@emcc24</p>

<p>Touch</p>

<p>kiruyama-correct
it’s straight doppler effect.</p>

<p>With the wind resistance on the foam ball, what is true immediately after the ball is released?</p>

<p>jeez I shouldn’t have tried to cram yesterday. I left 22 blank and guessed on 1. Hoping for >700. </p>

<p>what about the questions regarding the efficiency of a heat system? 360 K in and 270 out so it was 25% efficient, right?</p>

<p>Yep, 25% efficient is correct.</p>

<p>What did everyone put for average value on that graph? I used calculus and got 2.1.</p>

<p>for the foam ball I put that the acceleration decreases</p>

<p>it was much easier than those typo-infested PR practice tests I took last night</p>

<p>^wouldn’t that be true over time though? the question asked what was true at that exact instant.</p>

<p>also, what’s the curve on this thing? sparknotes has -9 as an 800, but i read that CB released a test that had -16 as 800.</p>

<p>oh yeah, what about the one where you had a pulley with a small mass on the table and a heavier mass suspended and then that same picture except with two small masses on the table. I think I left it blank, but I wanted to say that the acceleration was the same.</p>

<p>^acceleration was greater on the first picture because there was less mass opposing the hanging mass’s tendency to accelerate downward due to gravity.</p>

<p>did anybody get the quasars one?</p>

<p>i put they existed from the beginning of the universe</p>

<p>I put they release dimmer light because it takes so long for us to receive the light.
lol i didnt even know what a quasar was!
getting a lot i was unsure about right!<br>
i put 75% efficient because 270/390 = 75%</p>

<p>Ah, yeah that explanation for the acceleration one makes sense. Pretty sure I left it blank since I just couldn’t think straight.</p>

<p>There was one about relativity and the speed of light, too. I can’t remember what the question it asked though. </p>

<p>I’m probably going to retake this after summer. Gonna put some actual time (ie, more than one day) into preparing though… most of my problems were because I never took the time to stop and understand the concepts.</p>

<p>kiruyama, i dunno if this is the question u were talking aobut, but there was one about a spaceship moving at 2x10^8 m/s and shoots a laser beam at earth. and wats the speed of the light when its measured on earth?</p>

<p>and for part A, the graph questions are E and D? the v-looking graph and then the one that crosses the x-axis.</p>

<p>Speed of light is constant, so it should be 3x10^8.</p>

<p>Yes, I had E and D.</p>

<p>the speed of light is always 3x10^8 m/s, even if it is viewed from a different relative standpoint.</p>