# Search results

1. ### Number of Loops in a Solenoid

Homework Statement A solenoid has a radius of 10 cm and a length of 50 cm. What I need to know to begin the problem is the number of loops ion the solenoid. Homework Equations The Attempt at a Solution One turn will have a length of 2(pi)r. I need to know the thickness of the wire...
2. ### Spherical Solenoid

Thanks for the reply. I think I almost have it. But, when I am evaluating the integral, I think I'm having a problem with dl. The length, l, is 2(pi)r right? so dl would be 2(pi)dr? When I plug this into the integral and evaluate it from (0 to a) I'm off by a factor of 0.5. What am I...
3. ### Spherical Solenoid

Homework Statement A large number, N, of closely spaced turns of wire are wound in a single layer upon the surface of a wooden sphere of radius a. The planes of the sphere are perpendicular to the axis of the sphere (take axis to be horizontal), and turns are uniformly spaced per unit...
4. ### Synthesize propyne

I would like to know how to synthesize propyne from propane. I know there is a better answer (much better) than the one I put on my test. I said that propane should be exposed to a bromine solution in the presence of ultra violet light to create 2,2-dibromopropane. I then said to take this...
5. ### Planck's law for longer wavelengths

I was just working on a problem that asked me to show that Plank's Law for black body radiation is approximately equal to Rayleigh-Jeans Law, which expresses the energy density of black body radiation as a function of wavelength. I was to show that this relation is only true at high wavelengths...
6. ### Double integral with a circle connecting the two

Do you think you could expand on this a bit? In vector calculus, i'm at the stage where I mostly know how to solve problems and don't have a strong grasp on deep understanding. You know how math is, you learn how to solve problems first because of the pressure of tests and then as time...
7. ### Double integral with a circle connecting the two

Alright, starting to narrow it down now. Just to make sure, I can use the closed surface integral (the double integral with the hoop) whenever i'm working with closed, positively oriented surfaces, and I can use the triple integral with the hoop when doing something like Stoke's Theorem. Is...
8. ### Double integral with a circle connecting the two

Okay got ya. My only question now is that the only closed surfaces I have dealt with are when we use the Divergence Theorem to work with surfaces like a sphere. The Divergence Theorem is a triple integral though. Is it correct to use the symbol in question on the double integral in Stokes...
9. ### Double integral with a circle connecting the two

Yes that's the one! Was I correct at all?
10. ### Double integral with a circle connecting the two

I'm trying to figure out what this one symbol was I saw. I also have a guess that I would like to see if is correct. I saw a double integral with a circle connecting the two. What does this mean? Here is my guess. Is it used when dealing with Stoke's Theorem? Since ∫F°dS =∫∫ curl(F)°dS (Both...
11. ### Aluminum and iron(III) reaction

I was not expecting there to be a reaction between aluminum metal and a solution of iron chloride. I thought the aluminum would be oxidized and the iron reduced. What is the reaction that is occurring that is creating hydrogen gas on the surface of the aluminum? I know it has to do with...
12. ### How to calculate the Ksp

My lab group and I are a bit confused. We are doing a lab where we need to calculate the Ksp of calcium hydroxide in pure water and then in different concentrations of calcium chloride and potassium chloride to analyze the diverse and common ion effect. I was absent one day but my lab partner...
13. ### Enthalpy Of reaction

Im going to try my best to write out this chemical equation. Also I'm gonna write a forward arrow but it's really it should be the equilibrium arrows. [Co(H2O)6]2+ + 4Cl- --> [CoCl4]2- + 6H2O Sorry for that, I don't know how to use the math font or whatever it's called. The...

Thanks.
15. ### Dissolving silver carbonate

This is my last question on a prefab and I want to make sure this answer is correct. The question states; On the basis of LeChatelier's principal, explain why silver carbonate dissolves when nitric acid is added. I said it was because mixing nitric acid and silver carbonate will produce...
16. ### Activation Energy

We calculated k for room temperature by running two experiments, each one with the same concentration of dye but a different concentration of sodium hydroxide. We then set up a ratio of the two experiments to calculate the order of the reaction for sodium hydroxide. From this we calculated k...
17. ### Activation Energy

So we just completed an experiment and we are now expected to calculate the activation energy of the reaction we ran using our data. The reaction was between crystal violet and sodium hydroxide. The reaction was performed under pseudo order conditions (sodium hydroxide concentration did not...
18. ### Adult Swim China IL equation

Good to get that confirmed. I think the same question every time I watch that episode. True 1MileCrash. Futurama is one of the better shows for that. It's a shame there will be no more new episodes.
19. ### Adult Swim China IL equation

I'm not sure how many of you watch a show on Adult Swim called China IL but I have a question about it. The school wins the math competition and to celebrate they go out and destroy the town. Towards the end of the video someone spray paints an equation that is equal to anarchy and I'm not...
20. ### Prove if sin(1/x) diverges or converges

Sorry it took so long to reply. I believe I have the answer though. If I use the limit comparison test with 1/n as my series to compare I get the correct answer. I didn't know that you could use expressions within a trigonometric function as your series to compare.
21. ### Prove if sin(1/x) diverges or converges

The graph near zero is very intense. This is because the function will experiences infinitely many oscillations as it gets closer to zero correct? This problem is confusing. I can't use the alternating series test so my only option would be comparison like you said, correct? So I want a...
22. ### Prove if sin(1/x) diverges or converges

I'm sorry. Yes i'm talking about the sum you have written above from n=1 to infinity.
23. ### Prove if sin(1/x) diverges or converges

Both of you are saying exactly what I thought at first. I thought the function would converge because the limit of 1/x as x approaches infinity is zero. Sine of zero is zero. So I concluded that the sum converges. When I looked at the answer in the back of the book it said the series was...
24. ### Prove if sin(1/x) diverges or converges

I want to prove if sin(1/x) diverges or converges as x approaches infinity. I know the answer is diverge because the function oscillates. I want to prove it more rigorously though, for my own well being and for the exam coming up. I am having trouble with the ratio test and I rewrote the...
25. ### Graph for helium

I'm looking for a graph that shows me the root mean velocity as a function of temperature for helium gas. Does anyone know where I can find this? Thanks.
26. ### Percent copper in post-1982 pennies

That was a typo. I was looking at the wrong calculation in my calculator. I know how to find just and average density, it's 8.05g/ml.
27. ### Percent copper in post-1982 pennies

1234 ignore this
28. ### Percent copper in post-1982 pennies

What you must find out is how much copper and how much zinc it takes to make a penny which has a mass of 2.500 grams. You can use the mass of the new penny to figure out what the average density of the penny must be, given its mass of 2.500 grams. You also are given the densities of copper and...
29. ### Mass of Cu(UO2)2(PO4)2*8H2O required to contain 1.05g of P

Never mind. I calculated the same wrong molar mass twice in a row for the mineral.
30. ### Percent copper in post-1982 pennies

Well how do I get x unitless? I felt bad about not getting this problem but when I got to class turned out no one else I could find got it either. Are my equations even close to correct?