<p>I don't think the answer is either Copernicus or Newton, cuz if u google search their names, you can find they dealt with Waves/Optics</p>
<p>I just found out from the MathII thread that the curve for Physics has recently been 67 out of 75=800</p>
<p>Keep it up guys WE CAN BEAT THE MATH II THREAD</p>
<p>Kumara, I seem to be unable to find how Copernicus dealt with light or sound at all.
For Newton, however, I do know that he theorized the particle nature of light, and analyzed Newton's Rings.
Now the other guys I'm sure had something to do with light or sound, so I'm strongly leaning towards Copernicus.</p>
<p>I hope ur right qhausqkqh, cuz I put Copernicus too.....
I searched again, he seems to be famous in Cosmology or something like that?</p>
<p>It is most definitely Copernicus. </p>
<p>What did everyone put for the question about water, ice and vapor in a container?
What about the question with the 3 masses that are propelled by an explosion in the middle of them?</p>
<p>Oh and the question about the diameter of the earth and the gravity exerted on the moon?</p>
<p>the water, ice, and vapor become the same temperature?</p>
<p>the third mass has a velocity of 5 m/s in quadrant II.</p>
<p>For water, ice and vapor----I put they would all come to one temperature..
For three masses I used vector and I think the answer was 5 or something...
Wat did u put dag89?</p>
<p>I put in quadrant 4.......Crap, which one's right?</p>
<p>There was also a question that said something about heat engines according to the laws of thermodynamics. </p>
<p>I think I answered that heat engines cannot have 100% efficiency due to the 2nd law of thermodynamics.</p>
<p>For the moon and earth diameter, I think it was unchanged.....
But i think i am wrong, wat was the right answr?</p>
<p>I put Q4 also, but logic told me Q2.
I figured 7 m/s with the math, and chose A.</p>
<p>It's all coming back to me now...lol</p>
<p>For the questions in the beginning:
The graph for the feather falling in a vacuum was a y= mx graph.
The graph for a coin falling was a a graph that started off at a y=mx and then flattened out to a constant speed. I figured that happened when the air resistance became as strong as the force of gravity.</p>
<p>The graph on the mass on the two springs- this was a little later.
I think I put one that looked like a series of bumps.</p>
<p>dag89, there was no answer choice saying that they can't have 100% efficiency, but it's the same principle anyway...</p>
<p>I put that there will always be heat coming out of the exhaust.</p>
<p>I think it changes because an increase in diameter would also mean a decrease of the radius between the two masses. I think it should increase in some way, but I am not sure.</p>
<p>Air resistance varies with velocity.
can objects really have a speed limit as they free-fall?</p>
<p>I think it was worded like... a heat engine can never do the same amount of J as it gets in...or something like that...</p>
<p>Question number 5 in the sparknotes end of the chapter quiz in kinematics says so:</p>
<p>. E </p>
<p>The force of air resistance against a ball increases as the ball accelerates. At a certain point, the force of air resistance will be equal to the force of gravity, and the net force acting on the ball will be zero. At this point, its velocity will remain constant. This velocity is known as an object’s “terminal velocity,” and it explains why, in real life, many falling objects don’t continue accelerating all the way to the ground.</p>
<p>no the radius would NOT decrease. when you measure gravitational force/acceleration, you only pay attention to the centers (the cores) of each planetary body. even though the earth's diameter is doubled, its mass stayed the same (according to the question) and you only pay attention to its center, so the acceleration doesn't change.</p>
<p>acceleration=g=GM/r^2, where M is the mass of the earth</p>