<p>please discuss everything here...</p>
<p>My first question is, did anyone notice that number 75 is the most difficult?</p>
<p>I answered 71 and of those, guessed on 5.</p>
<p>For number 75, you take the work done by gravity (150N) minus the work done by friction (45N).</p>
<p>What was the scientists one? Newton or Copernicus?</p>
<p>And what was the phenomenon that lets us see light when the stars are below the horizon, cuz I put refraction.</p>
<p>Finally, was the student's experiment thing 4.1 and inaccurate due to air resistance?</p>
<p>Wow why did I not think of Newton's rings?</p>
<p>qhausqkqh: I got all the same as you. I put Copernicus for the scientist one. I put 105 J for #75.</p>
<p>How do you all think the curve will be? I'm hoping around -10 to 12 is 800 at least?</p>
<p>It wasn't that hard so I doubt it'll be too generous.
But then again the only tests I have to compare to are Barron's practice tests.</p>
<p>Oh and was the tank in a room thing at 20 degrees?
And the heat released 8*10^6 (I think it was to the power of 6) per hour?</p>
<p>lol it's so sad that math2 has 208 posts and we only have 6.
When are we allowed to discuss?</p>
<p>darn, I definitely got 75 wrong.</p>
<p>*praying for another 8-0-0</p>
<p>What was the answer to the question about the ball being thrown in the train cart?</p>
<p>Other questions,</p>
<p>Anyone know the answers of:</p>
<ol>
<li>Electric field in the paper (both questions)</li>
<li>After a long time, how much voltage goes across the capacitor.</li>
<li>optic instrument in the box</li>
<li>beats question</li>
<li>number of nodes in the closed pipe</li>
</ol>
<ol>
<li>question on why microwaves can't free electrons</li>
</ol>
<p>the ball-train cart answer was that both of the values stayed the same.</p>
<p>oh yeah, I hated the magnet-in-the-paper questions.</p>
<p>the voltage is the same as the emf</p>
<p>the optic question i skipped</p>
<p>the beats one is that the frequencies are different, amplitudes aren't (i think)</p>
<p>i skipped the nodes one.</p>
<p>its a flat mirrior in the box</p>
<p>theres 1 node and 1 antinode (antinode at opening, node at closed end), but i recall the question asking what the fundamental frequency was. I believe it was 50Hz, since the open pipe had 100Hz</p>
<p>Finally, was the student's experiment thing 4.1 and inaccurate due to air resistance?</p>
<p>Nope, if you're dropping things over such a short distance, the air resistance effects will be almost negligible. It is more likely that time is the greatest source of error (because the time is hard to measure precisely unless you have an excellent timepiece).</p>
<p>the ball-train cart answer was that both of the values stayed the same.</p>
<p>Stuff like that changes only when the reference frame is accelerating. Here it was at constant velocity.</p>
<p>The answer to the question that asked what the ratio of antinode to node in an open tube with a fundamental frequency harmonic was 1:1. This diagram shows the open tube with a fundamental frequency (top left diagram). <a href="http://www.eng.cam.ac.uk/DesignOffice/mdp/electric_web/AC/02375.png%5B/url%5D">http://www.eng.cam.ac.uk/DesignOffice/mdp/electric_web/AC/02375.png</a></p>
<p>The correct answer to the plane mirror question was:
1) virtual
2) upright
3) same size as the original object</p>
<ol>
<li><p>question on why microwaves can't free electrons
This is due to the photoelectric effect...the correct answer choice was because the photons of microwaves don't have enough energy to overcome their work function(they don't have a high enough frequency, and freq. is directly proportional to energy, so they don't have enough energy).</p></li>
<li><p>Electric field in the paper (both questions)</p></li>
</ol>
<p>One of the answer was a diagram in which field lines were moving in toward a single area (the question asked for a negative charge, and field lines are directed in toward a negative charge).</p>
<p>The other answer (asking for a parallel source of positive charges with a negative charge in its plane) was the choice that had parallel lines directed upward on the lower part and a sink of field lines above it.</p>
<p>beats-frequency similar but a little bit off and identical amplitude.
electric field on the paper-for the solenoid it's the one where the middle field lines add up and point to the right (was it A or E?) and the loop of wires is the other one where they look similar but the field lines loop at the top and bottom, and generally go to the left.</p>
<p>The potential energy ratio of Y to X was 2, and the maximum velocity ratio was 1, right?</p>
<p>Newton was a big proponent of a particle theory of light.</p>
<p>What about the one when two ppl. are standing on skateboard in ice and one pushes the other?</p>
<p>The pushing guy goes backward, the girl(?) goes forward</p>
<p>For the Scientists' question, I believe it was</p>
<p>"Which of the following scientists is not commonly associated with theories of sound and light?"</p>
<p>The word commonly emphasizes that the scientist is widely known for another field. That's why I put Newton.</p>
<p>That's what I put qhausqkqh...hope it's right...</p>