<p>i think the magnetic force made of parallel wires was C actually. This is because if you look at the equation e=vbl, the velocity and magnetic field were constant. Therefore only length matters and C had the greatest length.</p>
<p>Weren’t all the wired the same length? It’s just that the charges are traveling in different directions.</p>
<p>and what was the answer to the idea similar to a rocket launched?</p>
<p>right but C was the furthest on the top and therefore it had the greatest amount of wire below it</p>
<p>Oh I didn’t know it depended on the amount of wire BELOW… Why is that…?
Btw I put A for the rocket one, pushing a boat away from shore with oar</p>
<p>yeah i put A too for that, and i don’t really feel comfortable with my reasoning either, but if the velocity and magnetic field were all constant, what would differentiate the points? It was to be some kind of length. What else could it be?</p>
<p>For the rocket propulsion one it’s throwing rocks off of the boat. It’s akin to the burning and expelling of fuel propelling the rocket.</p>
<p>Moon: conservation of energy gives mgh = .5mv^2 <=> gh = .5v^2, right term is constant, g is six times smaller => h six time larger.
Orbit: f = g m1m2 / r^2 so if r1^2 = 1 and r2^2 = 9 then f2 = f1 / 9.
Pulley: same force => same mass
Minimum energy: E = fh = (c / l)h =~ 4 eV
Magnetic field with two wires: B = something I / r = constant, I two times larger => r two times larger.
Rocket: a rocket propels by ‘throwing’ away hot masses.
Wires in a field: The force is the cross product of the movement vector (tangent to the circle) and the field lines. Zero when parallel, maximum when perpendicular.</p>
<p>Not too sure about these:
Graph with pressure / volume: Internal energy = temperature?</p>
<p>oh I put charge E cuz it was traveling at ninety degrees to the magnetic field… Guessed haha</p>
<p>Btw I just looked up rocket propulsion, it said it uses mainly newtons third law, which means the answer is A</p>
<p>I think D made a better choice for the rocket ship question (throwing the rocks). I say this because the ship is losing mass, just like the fuel, and you control the thrust rate.</p>
<p>The pushing from the dock is a one time deal, and only gives you an initial velocity whereas the rock throwing is a continual effort until you run out rocks (much like what would happen when the ship runs out of fuel)</p>
<p>oh crap i think you’re actually right, totally forgot about the sin90=1</p>
<p>with the inclined plane, was it that F(tension)=F(perpendicular) and F(parallel)=f(friction)</p>
<p>Oh I thought it it asked for rocket propulsion from the ground, not the entire time haha oh well, I literally answered that question last minute</p>
<p>Yeah I think that’s right basketball1.</p>
<p>What was the one with the light shining through the lens on a flat piece of glass? It asked for what process made alternating light and dark “rings” in the glass and I put polarization.</p>
<p>Also, light microwaves and soundwaves: which can be diffracted?</p>
<p>Ahh got the rocket propulsion one wrong. I put that for the inclined plane one, basketball1. That way the parallel and perpendicular forces balance and there is no resultant force, hence a constant velocity.</p>
<p>Hopefully I didn’t get more than 10 wrong… I answered all the questions, so it comes down to silly mistakes and generally wrong answers…</p>
<p>EDIT: To the above poster, I put interference - it causes an interference pattern that creates bright and dark fringes due to superposition (I think).</p>
<p>I said that all could be diffracted.</p>
<p>Inclined plane was something like parallel=friction normal=perpendicular… Forgot the exact choice</p>
<p>Flat glass one was interference 100%</p>
<p>no onceanangel i think it was still A, rocket propulsion follows newton’s third law exactly, it’s just with a rocket the action is so great, that the equal and opposite reaction is also huge. Also to Pikafu and the alternating light and dark “rings” was because of interference i believe. and all three can be diffracted.</p>
<h1>$^%@</h1>
<p>Well I got those wrong then…sigh. My first guess was that all 3 could be diffracted. Should have gone with it.</p>