Ah, yes, precipitate. (Aren't bubbles just a gaseous precipitate, though?)
ERROR: The current state of the world is unacceptable. Save anyway? YES/NOI thought precipitate had to be a solid. I remember it because precipitation is when rain falls down, and gases don't fall (do they?).
Anyway, thanks!
That helped.
But now I have a Pre-Cal problem that is infuriating me.
"An airplane is flying at 400 mph at an angle of elevation of 30 degrees when it encounters a 50 mph wind. The resultant velocity of the airplane is 475.3 mph at an angle of 27.18 degrees. What was the direction of the wind?"
"War doesn't prove who's right, only who's left." "Every saint has a past, every sinner has a future."Angle of elevation? That strikes me as odd; sure it wasn't a bearing of 30º or something?
In any case, you basically have a vector addition (or subtraction) problem. The plane's original velocity plus the wind velocity will add up to the plane's resultant velocity. You'll probably want to convert the vectors to their component forms to subtract them.
I'm fairly sure that a precipitate is just whenever a chemical stops being dissolved...
Anyway. Zizoz speaks the truth.
ERROR: The current state of the world is unacceptable. Save anyway? YES/NOBreak the four hundred down into it's component parts, then find the differences between the horizontal and the vertical.
Fight smart, not fair.I assumed it was bearing, too. This is how I set it up:
Rx = 400cos(30) + 50cos(x) = 200sqrt(3) + 50cos(x)
Ry = 400sin(30) + 50sin(x) = 200 + 50sin(x)
475.3 = sqrt(Rx^2 + Ry^2)
So I squared both sides and did a ton of tedious algebra (which was probably where I made a mistake, though I can't see it) and ended up with:
20,000(sinx + sqrt(3)cosx) = 63410.09
Dividing by 20,000 gave me an unterminating decimal. I don't know what to do from here.
Edit: Fixed a transcribing error.
edited 11th Dec '10 8:21:00 PM by OnTheOtherHandle
"War doesn't prove who's right, only who's left." "Every saint has a past, every sinner has a future."First of all, those cos's in the equation for Ry should be sin's.
Secondly, you want to use the 27.18º. I think your method might work, but I don't think it's the easiest way.
Edit: Wait a moment, it's flying at 400 mph, it encounters a 50-mph wind, and it ends up faster than 450 mph? I don't think that makes sense...
edited 11th Dec '10 7:59:40 PM by Zizoz
The angle method is definitely the way to go, but I'm with Deboss thinking the magnitudes of the velocities are off and you're going to get peculiar junk answers.
Think of it this way. The plane is going 400 mph. Depending on the direction of the wind, that can only alter the velocity +/- 50 mph at the most. Even if the 50 mph was a tailwind pushing it exactly in the direction it's already going, it wouldn't get up to 475.3.
Even more worrisome is this question has an overloaded amount of data. Given the final flight angle or magnitude of the wind, the Rx and Ry equations would be sufficient to calculate the missing one and the direction of the wind. But giving both means that you now have two equations and one unknown, and unless they picked their constraints very carefully they're quite likely to be inconsistent with no common solution.
So at this point you should probably smack your teacher.
edited 12th Dec '10 12:55:47 AM by Pykrete
Maybe the point of the quesetion was to get us to realize that it was impossible. That seems like something he would do.
Anyway, thanks for the help, guys.
edited 12th Dec '10 8:24:38 AM by OnTheOtherHandle
"War doesn't prove who's right, only who's left." "Every saint has a past, every sinner has a future."The only way I could think of it getting you even better velocity is if it was a head wind (?) and forced more air into the engines increasing output. But that seems a little advanced for a physics class.
Fight smart, not fair.Yeah, we never talked about anything like that. It's a math class, too, so we don't usually go for the kind of accuracy of physics classes. Like we just decided that the speed of sound was always 740 mph for the purposes of our calculations.
"War doesn't prove who's right, only who's left." "Every saint has a past, every sinner has a future."Yeah, I mean if you wanted to go for the Fail Hat Trick tell him drag forces don't work that way, but that seems overly pedantic for the sake of the kind of math you're obviously supposed to be doing.
It may or may not have been a deliberate trick question. I've had profs douchey enough to do that stuff on purpose, as well as ones who have made worse mistakes on accident because their brain was fried after six hours of grading stuff when they wrote the question.
Also, there's a difference between "impossible to solve" and "inconsistent conditions". This is a case of the latter, when using the given numbers returns nonsense or an outright contradiction. Impossible to solve would be something like having too many unknowns for the amount of constraints you have.
edited 12th Dec '10 2:58:43 PM by Pykrete
My advice would be to just ignore the velocity component of the wind. The rest is doable without it.
Fight smart, not fair.So if I used the angle it would be 27.18 = arctan(Ry/Rx), right?
So tan(27.18) = (4 + sinx)/(4sqrt3 + cosx)
But now what? I don't see it.
Edit: Never mind, I do see it! Is this right?
sin(27.18)/cos(27.18) = (4 + sinx)/(4sqrt3 + cosx)
And then you would treat it like a proportion, right?
Edit agian: Yay! I got an answer that worked when I plugged it back in! Thanks, everybody!
edited 12th Dec '10 4:08:31 PM by OnTheOtherHandle
"War doesn't prove who's right, only who's left." "Every saint has a past, every sinner has a future."How does the first part of this essay look? Are there any awkward phrases or pointless sentences? Am I being redundant?
To transcribe what one believes is a surprisingly difficult task. Although we may have a vague idea of the concepts we support, the actual task of defining those concepts on paper becomes nearly impossible when given a moment of thought. The most significant reason for this is that most individuals hold contradictory beliefs. As said by John Updike, “A person believes various things at various times, even on the same day”. This ambiguity is a testament to our humanity. To strip one of their uncertainties would be to strip one of their humanity. Thus, while I cannot say I believe absolutely, I do think that uncertainty is the engine which drives humanity forward.
First, humanity strives to feel whole. In 2009, in response to the recent bombings on the Gaza Strip, Queen Rania of Jordan declared that, “humanity is incomplete”. With so much confusion and uncertainty in every aspect of our lives it is hard not to agree with her. Fiction toils over this fact and nihilists write entire novels on the issue. Most believe that the apparent lack of a defined goal for our species is a curse. I believe, however, that uncertainty is a strength rather than a flaw. Although we want to eliminate this ambiguity in our daily lives, the task is Sisyphean. The moment one question is answered, a dozen more mysteries appear. While completely infeasible, this quest for knowledge and a sense of wholeness drives us forward. If we were truly complete, society would become stagnant as there would be nothing left to accomplish.
First rule of writing essays is: break any rule if doing so will make it easier for the reader to understand your point.
The Philosopher-King ParadoxEh... I'll have to disagree with you on that point. Stylistic things like that are generally there for a reason, and breaking them can make it not really an essay anymore. But that's just my experience - the rules for essays may be different in whatever subject that is. If the topic is "What I believe" perhaps it's expected.
Just as long as the teacher/lecturer isn't going to take marks off for it.
Be not afraid...

Ummm... Change in color or conductivity?
ERROR: The current state of the world is unacceptable. Save anyway? YES/NO