December Physics SAT2 Thread

Test Preparation SAT Subject Test Preparation
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<p>For the particle with the non-zero mass I also said electron, though I don’t remember anything more specific about the question.</p>

<p>For the electric potential, the one that went around the circle but not any closer to the center did no work.</p>

<p>I don’t remember what charge the particle was that was being moved around the center; if it was positive then work was done by moving it closer to the center so the one where Y was closest to X was the one with the most work.</p>

<p>For the weight of the man when the radius of the earth was doubled use F = GmM/r^2, where F is the weight…though, now that I think about it, if you double the radius the weight would decrease by a factor of 4, and intuition says that the heavier something is, the more an object on its surface would weigh. I remember writing that the weight increases by a factor of four, but I can’t give a rational explanation =&lt;/p>

<p>Princeton Review didn’t say anything about focal length vs index of refraction so I have no idea - I said that the focal length gets shorter, just because it seems more correct.</p>

<p>SUMMARY:</p>

<p>Q: Which scientist is not correctly matched with a topic they researched?
A: Galileo and Heat Engines</p>

<p>Q: Particle with smallest mass:
A: Electron</p>

<p>Q: 3 of which particle together forms another particle?
A: Quark.</p>

<p>Q: Which standing wave was not possible?
A: The one whose antinote (peak) was not in the center. Don’t remember which choice. (Ashyda)
A: the one that had two harmonics (laure327)</p>

<p>Q: Diagrams in which a particle forms a somewhat circular path around a source charge: In which diagram does the external force do no work?
A: The one where the particle only went around a circle around the source charge, and did not get closer to it.</p>

<p>Q: Same diagram as previous question, which one does the most work?
A: The one in which the distance between X and Y is smallest.</p>

<p>Q: What is the weight of the man when the radius of the earth is doubled?
A: 4x his original weight (unconfirmed)</p>

<p>Q: What happens to focal length when a lens is moved from air to water?
A: It gets shorter (?)</p>

<p>Q: Last question - frictionless hockey puck is moving east, it gets hit by a force for a given time and then the force stops
A: Puck went straight east, then parabolically south with a concavity pointing upward, and then when the force stopped, the puck went in a straight line tangential to the direction it was going when the force stopped acting.</p>

<p>Q: What stays constant as a satellite orbits earth? <strong>DOES ANYONE REMEMBER THE CHOICES?</strong> I think one of them was acceleration…
A: 2 people for angular momentum</p>

<p>Q: What’s an example of a conductor and an insulator?
A: Aluminum and Glass</p>

<p>Q: Electroscope with an equally distributed positive charge, the pieces of aluminum inside attract eachother, what is the rod held toward the electroscope?
A: Negatively charged conductor?</p>

<p>Q: ??
A: Satellite will not approach earth because of its existing velocity.</p>

<p>Q: Something with an ideal heat engine
A: 110J or 0J</p>

<p>Q: Something with fire.
A: Converging Lens?</p>

<p>Q: Two people and a police car, the car is in the middle of the two. Person A is on the left, Person B is on the right. Which person hears a greater frequency when: ??
A:</p>

<p>Q: Some graph of a parabola, I think it was distance vs time. Peak is at t = 3
A: At t = 3, a = -10 and velocity is 0.</p>

<p>Q: Some other graphs with a similar situation as the previous question, idk the Q.
A:</p>

<p>Q: In the same line, an object is moving and hits another one at rest (no friction). What is the ratio of the two velocities?
A: I think I said that you have to know the masses of the boxes. (m1v1 = m2v2)</p>

<p>Q: What is proof of an expanding universe?
I. Red Shift
II. Something with radiation
III. Something about planets orbiting around the sun
A: I put I and II.</p>

<p>Q: Two boxes hit, one is coming from the west and one from the south, is KE or momentum conserved?
A: I said that KE and momentum are conserved</p>

<p>Q: What is the frequency of the doppler effect?
A: The difference between the frequencies of the two contrasting pitches.</p>

<p>Q: In a badly made speaker, there is a faint hum when a certain pitch is played due to…
A: Resonance</p>

<p>Q: Change in voltage over the resistor on the right?</p>

<hr>

<p>I I I
I R = 3 I
battery I R = 3
I R = 6 I</p>

<h2>I I I</h2>

<p>A: V = 6V?</p>

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<p>no that makes perfect sense, i left it blank, and thank god bc i wouldn’t have put that. i put 1,2,3 also, and the last one was an oppsing force or something and i put the one that started high and ended with 0.</p>

<p>With the one for the voltage difference, did you guys say 6V?</p>

23

<p>for the quark one, i left it blank but this is what wikipedia says…</p>

<p>A proton = composed of two up quarks and one down quark</p>

24

<p>I put photon for the rest mass//// ****</p>

25

<p>I said mechanical energy because I think the law of conservation of mechanical energy says that mechanical energy is conserved for frictionless systems.</p>

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<p>also i think the weight of the man was quarter of his original weight. As the radius gets bigger the force gets smaller by 4, and if you look at the equation F=ma, m is constant so that means a will go down by 4 as well. So W=mg (ma) and therefore weight would be W/4…if that makes sense</p>

<p>and great summary Ashyda</p>

27

<p>thanks a lot asyda!</p>

<p>Q: What is proof of an expanding universe?
I. Red Shift
II. Something with radioactivity? I think…
III. Something, I thought it was wrong</p>

<p>I said red shift and radiation. the last choice was planets orbiting around the sun, which is wrong i think.</p>

<p>for that momentum question, i said it would depend on the ratio of the masses</p>

<p>Q: Two boxes hit, one is coming from the west and one from the south, is KE or momentum conserved?</p>

<p>i said only momentum is conserved. i might be wrong though!</p>

<p>anything else? btw, what do you guys think the curve will be like?</p>

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<p>Q: Two people and a police car, the car is in the middle of the two. Person A is on the left, Person B is on the right. Which person hears a greater frequency when: ??</p>

<p>Whichever person it moves towards hears a greater frequency because of the doppler effect I believe</p>

29

<p>but what was the answer for the ideal heat engine…110J or 0J?</p>

30

<p>thanks for your opinion. but would PE be greater enough to replace the loss in KE?</p>

31

<p>I think like a 57+ raw will be an 800. I thought it was slightly more difficult than past ones. This is based off the 59+ raw = 800 from the subject test prep book.</p>

32

<p>for the curve, is -10 usually 800?</p>

33

<p>The curve is usually about 15 questions, so 60/75 raw score. That’s about 11Q wrong. Hopefully the curve here is generous…</p>

34

<p>ya i hope so :)</p>

<p>btw, for Q: In a badly made speaker, there is a faint hum when a certain pitch is played due to…
i chose beat. am i wrong for this one?</p>

35

<p>this test was definitely more challenging than ones i took before, I think a raw score of 59 will be an 800</p>

36

<p>Oh and I’m editing my first summary thing rather than reposting every time. So if there are updates it might not be obvious.</p>

37

<p>and for the beat, i chose “difference” one.</p>

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<p>For the badly made speaker, I’m 90% sure the answer was resonance.</p>

<p>It definitely was not beat, because you need two different frequencies to produce a beat.</p>

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<p>don’t worry ashyda. thanks for your work :)</p>

<p>basketball1, really? i thought it was easier than november one… but i hope the curve is lenient! :)</p>

40

<p>did anyone get 2v for a question,</p>

<p>and did any get an angle of 90 for a magnetic field question</p>