<p>did the question about the photelectric effect show that light has particle like properties</p>
<p>
[quote]
Einstein got the Noble prize for the photoelectric effect in which he showed that light can behave like a particle.
[/quote]
</p>
<p><a href="http://qd.typepad.com/bigidea/%5B/url%5D">http://qd.typepad.com/bigidea/</a></p>
<p>I put 1/9</p>
<p>the radius is 3 times the radius of the earth, so why 1/4?</p>
<p>the center of the circle is the center of the earth so 3R + R = 4R</p>
<p>???????????</p>
<p>I think it should have sth to do with the square of (nR) what ever n is .</p>
<p>g' = 1/9 g
Potential energy decreases
Light has particle like properties
Spaceship: had no idea; just guessed</p>
<p>i left the spaceshuip one blank</p>
<p>light has partivle-like properties, very sure of this..</p>
<p>what is 1/9?the one i was talkingabout?</p>
<p>potential decreases?</p>
<p>what is that?</p>
<p>I think the spaceship question had to do with relative speeds, right? Something like (v1 + v2) / (1 + (v1*v2)/c^2))?</p>
<p>I don't remember the exact formula, but the idea was that the probe was travelling faster than the spaceship, since the people in the ship saw the probe pass by at 0.6c... That would mean that the probe is going faster than the ship (0.7c), but slower than the speed of light (c), which is the fastest speed attainable, yeah?</p>
<p>And RC, I think you're right about the chart with speeds at various times. It travels at a constant speed at first, then has a constant negative acceleration... I think it had to do with friction.</p>
<p>The question about the centripetal acceleration of something of the satellite was indeed 1/9, I think. I think they said the radius of orbit was 3R, not that it orbited 3R away from the surface of the Earth. So yeah, 1/3^2 = 1/9.</p>
<p>Btw, does anybody have the blue book score conversion for Physics?</p>
<p>yeah, hopefully its 1/9</p>
<p>so.. what were some other questions that u guys found to be hard??</p>
<p>what was the answer to that question with: current I and 2I traveling upward and a point P in the middle. If the distance from the point to current "I" is "L," what is the distance from current 2I to point P??</p>
<p>I skipped it by accident</p>
<p>yeah, 2I...............</p>
<p>DinaZhang:
1/9 for the gravitational force on the satellite or something
Potential energy decreases for the object sliding down a curve.</p>
<p>potential energy decreases but the force exerted by the surface on the ball increases as the ball slides down the quarter-circle...</p>
<p>and the wet road thing was because light gets reflected in all directions... i've put in total internal reflection though!</p>
<p>Not TIR cause TIR only occurs from slow->fast, right?</p>
<p>I was about to choose total internal reflection, but I looked at the wording of the choice and realized that TIR can't occur when light hits the water...</p>
<p>mm... wish i realized that during the test</p>
<p>yeah, thanks...</p>
<p>now regarding the spaceship problem, spaceship is traveling 0.7c relative to earth ,i.e when the earth is at rest, spaceship is moving @ 0.7c . now probe is moving 0.6 c relative to spaceship, i.e if the spaceship is at rest, it moves @ 0.6 c =>speed of probe w.r.t earth = 0.6c + 0.7c = 1.1c (choice E : c < speed)</p>