<p>Wasn’t answer 2?</p>
<p>150N/10(m/s^2) = 15kg; 180N-150N = 30N, 30N/15kg = 2 m/s^2</p>
<p>Thanks for confirmation</p>
<p>Alright, I took AP Physics B last year, and Physics C this year in school, and found the subject test to be no problem. I didn’t omit any, but was unsure on about 4 of them.</p>
<p>The waves/boat question was one of them. Since the distance between each of the waves is equal, the boat is travelling at the same speed as the waves. (but not sure)</p>
<p>For the prism air/water/glass refraction question, the answer is that the angles are lesser, since the index of refraction is closer to that of glass. </p>
<p>For airplane question, the net force is 0. The plane is neither accelerating nor going up/down, so NET force is 0.</p>
<p>The the lens where the object is placed close to the convex mirror, the image is virtual, upright, and larger.</p>
<p>For the lightbulb question, the current through D increases when you removed lightbulb B because the Req of the parallel circuit decreased, so the total Resistance of the circuit decreased, and using V=IR, the current must increase with a decrease in R.</p>
<p>To find the voltage across bulb D, the voltmeter must be in parallel with D. Did this in Lab numerous times.</p>
<p>For planets X and Y, where planet X was twice the mass of Y, the F=0 point was between the two planets, but closer to the smaller planet Y, since each planet has attraction forces at field=GM/r^2, so the object has to be closer to Y.</p>
<p>The distance between the trees is 90m, since you just take the integral of the v vs. t graph between the time intervals. (Area of the trapezoid).</p>
<p>The last question was just conservation of energy. mgh + .5mv^2 = .5m(vf)^2 + friction. The answer as I recall was 36J.</p>
<p>For the efficiency problem, Efficiency is work done/work intake=200/800=25%</p>
<p>For the object that weighed 150N and felts 180N of force, you first had to find the mass of the object. W=mg=150 –> m=15kg.
Net Force=180-150=30=ma –> 30=(15)a –> a=2m/s^2</p>
<p>Hope this helps!</p>
<p>the block one:</p>
<p>i believe it was weight: 150N <– from that you know that mass is 15kg
upward force: 180N</p>
<p>net force: up - down = 30N
30 N = 15 x acceleration
aceleration = 2m/s^2</p>
<p>i got 1.2 as well, did everyone have that?</p>
<p>@scohajo:
Why did you do 180-150?
Uh oh, I guess I got this one wrong.</p>
<p>…wooops im late, haha so many posts while i type…</p>
<p>For the prism one, if n of the water is greater than n of the air, doesn’t that mean it will refract less? I thought that you refract more if the ns are really different, and refract less if they aren’t off by much. I guess I got my concepts wrong.</p>
<p>anyone get somethin w a glass block?</p>
<p>The one to measure using snell’s law was A, which was use a laser/light and a glass block. NOT a mirror.</p>
<p>Correct?</p>
<p>@Abrayo, which exams did you take? you’re on other threads too :p</p>
<p>I took math II, chem, physics</p>
<p>^ same here, skepticidal.
Order of difficulty for me was Math (D:!) > Physics > Chem.
But Chem has a harsher curve so I don’t know.
You?</p>
<p>@Abrayo, do you remember if there were more options (roman II’s) or was it straightforward
because if it was straightforward i said glass block…</p>
<p>and did we get relativity (D) for an answer?</p>
<p>I dispute the claim that the water will make the angles wider. If the water had an index almost that of the prism, the light would go straight thru the prism, making smaller angles.</p>
<p>What was the answer to what causes the plane waves to spread over a wider arc? I knew that decreasing the hole length was one answer, but was II or II also possible?</p>
<p>It was straightforward.</p>
<p>zkaplove17, no idea what you’re talking about?</p>
<p>@garfieldliker:
I hope you’re right, I said smaller angles as well.</p>
<p>Regarding the plane waves one, I know I put decreasing the hole length as well. I think another option was changing (inc/dec?) wavelength or frequency? Maybe? I don’t remember what I ended up putting.
I think I said increasing wavelength as well as smaller hole.</p>
<p>That’s what I put</p>
<p>Mine was…</p>
<p>Chemistry > Math II > Physics</p>
<p>This was my second time taking math II 
i do so well on practice exams but I get very nervous and am horrible at actual test situations… What order did you take them? I took physics, math, then chem</p>
<p>@Abrayo, the Snell’s law experiment question is correct: laser and glass block.</p>