<p>What occurs in light waves in air but not sound? I think the options were diffraction, polarization, interference, resonance, and dispersion.</p>
<p>Polarization</p>
<p>Darn I missed that one. I remember one question about an electroscope but I don’t remember the premise…</p>
<p>the electroscope was charged negatively, then they bring a sphere next to it and the leaves move closer together. ball=positive charge</p>
<p>Wouldn’t the ball be negatively charged, since the leaves moved away from the ball?</p>
<p>nice, that was my reasoning. anything you guys were unsure of?</p>
<p>I dont think air polarizes light</p>
<p>" Electromagnetic waves, such as light, and gravitational waves exhibit polarization; acoustic waves (sound waves) in a gas or liquid do not have polarization because the direction of vibration and direction of propagation are the same."</p>
<p>Wikipedia never lies.</p>
<p>The question is does light polarize in the air. Not if it polarizes.</p>
<p>@dinero</p>
<p>the leaves move closer. it said that in the problem and showed it in the diagram. which means the negative charge was reduced</p>
<p>do waves travel through solids? for a different electroscope one, if the leaves are both positive and move away from each other when a rod is brought close to them, is the rod negative?</p>
<p>@above. Waves travel through solids. And anyone remember the second to last question regarding a bunch of particles being shot into a rotating container? Answers revolved around what measurement could be deteined (mass, velocity, charge,some others )</p>
<p>I put speed</p>
<p>speed 10char</p>
<p>I thought it seemed pretty reasonable. I’m hoping for an 800 but I think I probably got more like a 750 to 770.</p>
<p>for the constant/changing questions,</p>
<p>it was magnitude of force, either direction or magnitude of accel., and angle between F and v</p>
<p>was it direction or magnitude of acceleration?</p>
<p>Direction of acceleration</p>
<p>What was the answer to the one about students climbing stairs and power expended? Was it the heaviest one?
And zero acceleration means direction and magn is not changing?</p>
<p>Ugh I thought it was pretty hard.</p>
<p>Two things: any bets on the curve and when do we get our scores? Thanks.</p>
<p>I didn’t know, but I guessed and said heaviest</p>