Math Is Fun Forum

Actually, it does. R is the ideal gas constant, which can be expressed in units of energy/ temperature*mole, which is also the units of heat capacity.

They've given you the heat capacity like it's a constant, which it isn't. Heat capacity is a function of temperature. Also, they've asked you to assume heating at a constant pressure, which you can't because the pressure is going to change when you heat the gas in a closed volume.

What class is this for? I ask because I don't know how far to go with the solution. It doesn't seem to be the type of problem that you'd get in a math class, but other classes (chemistry, engineering) don't usually make such gross oversimplifications so I'm wondering if this is really the whole problem.

Anyway, we'll take them at their word. Since we don't have Cp as a function of T, we can just multiply it by δT to get the specific internal energy change δÛ, which has units of energy/mol. Then just multiply that by the moles of gas, found as n = PV / RT = 0.1 (L*atm) / R (L*atm/K*mol) * 300K .

That should get you the very approximate solution. If you need the real solution I can get that for you too. (This is what I get for studying Chemical Engineering. )

Hmm...that seems much too nice and neat to work. To check for sure, you'd need to find the total heat in the system and then convert that to temperature for 60g of water. I'll do that in the morning as I don't remember how off the top of my head and right now I don't have my book handy.

Profit and loss both have the same formula. Profit is positive and loss is negative. I'll use the symbol "N" (for "net", as in "net profit" or "net loss") to denote that quantity.

N = Revenue - Costs

You may need to solve some equations for both the Revenue and Costs terms. If you need a percent, then do:

(N/Revenue) * 100%.

...which gives you the percent excess (or deficit) revenue.

I'm with the student in the last image of Toast's post. (S)he answered the question as asked. It absolutely infuriates me when teachers ask things in such an ambiguous way that you have no idea what to do.

My other favorite is "discuss"--"Discuss the function f...". The only sensible response is, "What about it do you want to know?" But you can't very well put that if you expect points on the assignment.

Yes, I'm bitter.

D'oh! I forgot the chain rule. Thanks Jane.

Gosh. It's late, but I'll have a go. (Sorry if some of my answers are snarky, but the questions are a bit redundant.)

1. Synthetic division is a quick way to perform polynomial division. It lets you determine the coefficients of the polynomial that will result from from dividing one polynomial into another.

2. Uh...Students? Math nerds? You?

3. To perform polynomial division quickly. This is extremely useful for factoring higher order (degree 3 or more) polynomials, and can occasionally be useful for algebraically reducing some functions (those composed of a quotient of functions usually).

4. See 1.

5. Synthetic division is MUCH faster than polynomial long division, if you can remember how to do it (I never can; who factors polynomials by hand outside of algebra tests?).

6. Insufficient information to answer the question.

For more on synthetic division, see http://www.purplemath.com/modules/synthdiv.htm .

I personally can float on my back in ordinary water. I would imagine quicksand would be the same.

Thanks; I got full credit.

Antimatter production has at least one very worthwhile use: as rocket fuel. Not even just to power the warp drive on the Enterprise, but because it is the most energy-dense power source in the universe. We are currently limited in our space exploration by the energy density of our rocket fuel; if we had a reasonably priced way to produce antimatter, we could send a probe to neighboring star systems...

Unless, of course, the scientists are too beholden to this "law" of conservation of energy to see the fundamental truth. Everyone knows that laws are really more like "guidlines" than actual rules.

Kidding! I'm with you. Their info page has this to say about independent verification:

None will publicly go on record? Why could that be? The only reason not to is that you are concerned about your reputation. Wait...either the technology works, or it doesn't. If it works, there is no danger (and actually a lot of prestige) in going on record to support it. If it doesn't work, then you should go on record to decry it. Which option did anyone choose?

This leads to the conclusion that the whole thing is a big, elaborate hoax. However, I'm having a hard time following the money here. What does Steorn stand to gain from the deception? They apparently have a history of doing business in an entirely different market (counterfeit prevention technologies). Why would they want to destroy their credibility with a lie?

I'm not 100% sure, but I think batch files are more analogous to Unix shell scripts, which Macs can also run.

Applescript is for GUI applications. Think VBA in Microsoft Office, only on a global system level.

That's scarily coincidental and hilarious all at once... .. ....!