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1. ### Chemistry Calulating Atomic Percentages given moles and weights of compounds

Homework Statement This is the statement out of a paper: Slurry 10 grams of ZnS with 3mL of .2N Cu(CH3COO)2 solution (corresponding to 0.6 atom % Cu) and 1.7 mL of .2N NH4Cl solution (corresponding to 0.34 atom % Cl) So my question is how did they calculate the .6 at. % and .34 at. %...
2. ### Concentration and pH Caculation of Titrations

Homework Statement Calculate the volume of 0.116 M HCl(aq) required to neutralize the following solutions. all the hydroxide ions in 25.0 mL of 0.215 M KOH(aq) 1. What is the molarity of Cl - ions at the stoichiometric point? Homework Equations HCl + KOH --> KCl + H2O The...
3. ### Electric Field and Charge of a Capacitor

Thank You, I figured it out
4. ### Electric Field and Charge of a Capacitor

Tell me if I'm headed in the right direction since we are dealing with an electron I know the charge therefore should be able to figure out the electric field using the F=qE formula. |F|= 5.6e-14N q= -1.6e-19C E=350,000 N/C
5. ### Electric Field and Charge of a Capacitor

I am sorry but can you tell me how I would go about calculating the strength of the field. I assumed you would have to know the charge first to figure out the strength.
6. ### Electric Field inside a metal sphere

Homework Statement A solid metal ball of radius 1.5 cm bearing a charge of -16 nC is located near a hollow plastic ball of radius 2 cm bearing a uniformly distributed charge of -4 nC on its outer surface. The distance between the centers of the balls is 8 cm. What is the electric field...
7. ### Projectile problem help

When your calculating the speed at which he must move remember that he is already 10 meters away, just a thought.
8. ### Help with Motion?

Well if you plan on using your graphing calculator: you simply graph the function and use the calculators min/max function to find the x value at which it reaches maximum height, which corresponds to the peak of the parabola. Or if you know some calculus you can always take the derivative of the...
9. ### Electric Field and Charge of a Capacitor

Homework Statement In a cathode-ray tube (CRT), an electron travels in a vacuum and enters a region between two "deflection" plates which have equal and opposite charges. The dimensions of each plate are L = 13 cm by d = 4 cm, and the gap between them is h = 2.5 mm. During a 0.001 s...
10. ### Field and force with three charges

Oh yes your right, I just kept converting the cm to m wrong, putting an extra zero in front of it like they were mm or something. Thank You so much it really helps having someone else look at this. I knew I had to be making some stupid mistake.
11. ### Field and force with three charges

The components of the positions are in centimeters. (cm)
12. ### Field and force with three charges

Homework Statement At a particular moment, three small charged balls, one negative and two positive,are located as shown in the figure. q1 = 3 nC, q2 = 7 nC, and q3 = -5 nC. What is the electric field at the location of Q1, due to Q2? y q1 | | | q2______q3____x Okay...
13. ### Electric Field of a dipole

Oh I think I figured out where I went wrong I forgot to cube d,
14. ### Electric Field of a dipole

Homework Statement A dipole consists of two charges +q and -q, held apart by a rod of length s, as shown in the diagram. If q = 4 nC and s = 2 mm, what is the magnitude of the electric field due to the dipole at location A, a distance d = 5 cm from the dipole? The diagram shows point A...
15. ### Calculating Electric Fields

Yes the |r|^2 was dubious After reworking that I got |r|=1.6882e-8 Plugging this back in I get E=[9e9*(1.602e-19)/(1.6882e-8)^2]*< -0.5923, 0.4739, 0.6516> =<2996700,-2397300,-3296300> Is this a more reasonable answer?
16. ### Calculating Electric Fields

Homework Statement A π- ("pi-minus") particle, which has charge -e, is at location ‹ 5.00e-9, -5.00e-9, -6.00e-9 › m. What is the electric field at location < -5.00e-9, 3.00e-9, 5.00e-9 > m, due to the π- particle? 5e-9 is equivalent to 5*10^-9 Homework Equations E=(k*q/r^2)r-hat...
17. ### 2 Dimensional Motion

Okay I figure it out i was doing it right but when it cam e to combining the two components i was just adding them instead of finding the magnitude for velocity. Which involve taking the sqaure root of the squares of the components.
18. ### 2 Dimensional Motion

Homework Statement A sailboat is traveling east at 5.0m/s. A sudden gust of wind gives the boat an acceleration a =(0.80m/s^2) (40 north of east). Homework Equations What is the boat's speed 6\;s later when the gust subsides? I know the answer is 9.21m/s, but I am having...
19. ### Balancing Chemical Equations with Linear Algebra

Homework Statement Balance the following Chemical Equation (x1)KMnO4+(x2)MnSO4+(x3)H2O->(x4)MnO2+(x5)K2SO4+(x6)H2SO4 Homework Equations Here is the matrix I came up with but it seems to be flawed but I am unable to see what i am doing wrong 1 0 0 0 -2 0 (K) 0 1 0 -1 0 0 (Mn) 4 4 1...
20. ### Iron-oxide (rust) making question

Just curios jhony did you happen to get the instructions from the cookbook, because if you did you know its a load of crap right? Just a warning. But it is possible to make good amounts of rust with a decent power supply. You have to connect the positive lead to what ever you want to turn to...
21. ### Run in with the law

yeah i always thought opening mail that doesn't belong to you is illegal but the police officer's explanation was that the person who received the package wasn't wearing his glasses so he did not see the address. which i think is a load of bs. But i am not to worried about it since the package...
22. ### Run in with the law

Ok today i had an officer deliver a package to my house. He also preceded by asking one of the my fellow residents what the package contents were and why it was ordered. Apparently UPS delivered the package to the wrong address and that person opened the package and didn't know what the...
23. ### Could a '28 Days Later'-Like Virus Ever Exist?

Thank you for sharing your thoughts and ideas. I guess with advancements in genetic engineering something similar to the rage virus could be developed. Probably not as deadly as the rage but similar enough to be a threat.
24. ### Could a '28 Days Later'-Like Virus Ever Exist?

Not sure where this post belongs, but anyway i was wondering if a virus such as the one depicted in 28 days later could ever be developed or evolve from some virus that we know of today. From what i know i think viruses are capable of evolving because when i read the hot zone it talked about a...
25. ### How to properly use an ammeter to monitor an electrolytic cell

Thanks I just tested it out and it works great. i appreciate your help everyone
26. ### How to properly use an ammeter to monitor an electrolytic cell

Just to make sure is this what you mean: http://s106.photobucket.com/albums/m261/Squall_11/?action=view&current=Ammeter.jpg Thanks A lot
27. ### How to properly use an ammeter to monitor an electrolytic cell

Hi i recently acquired an ammeter with a shunt can anyone explain how to wire this so i can measure amps in an electrolytic cell. Does the positive lead have to be wired across the shunt so that it doesn't burn out the lcd display. I've never used such an ammeter so any suggestions will be...
28. ### Make a Magnetic Stirrer: Fix Flea Spinning Problem

Just wire it up works great Thanks a lot
29. ### Make a Magnetic Stirrer: Fix Flea Spinning Problem

Thank you Integral that's a lot easier than trial and error.
30. ### Make a Magnetic Stirrer: Fix Flea Spinning Problem

I have a potentiometer but I don't exactly know how to wire it. I remember messing with it a few months ago but i hooked it up by trial and error. It has three prongs they're not labeled. If some one could explain how it works i will appreciate it.
31. ### Make a Magnetic Stirrer: Fix Flea Spinning Problem

Hi i am trying to make a magnetic stirrer. I have seen tutorials on how to make a magnetic stirrer from a pc fan and magnets. i have actually constructed such a device, but the results I got were less than satisfactory. My problem is that the flea used to stir the solution doesn't want to spin...
32. ### Copper Impregnated anodes

I have not tried linseed oil yet but I'll probably give it a shot. I have a question about using NaCl solution the question is how can i know when most of the NaCl has been converted to NaClO3 if it doesn't precipitate out. Are there ways of checking the NaClO3 concentrations in solutions.
33. ### Copper Impregnated anodes

Ok I see your right it does percipitate out while the cell is operating and i guess i do loose a good bit of product in the filtration process. You said it the precipitant causes the cell to dissipate more energy and heat could this be a cause for excessive anode wear. any way thanks for the...
34. ### Copper Impregnated anodes

Thats what I assumed, thanks for your reply, but i do have another question why is it better to use NaCl then do a double replacement does that result in higher yields. I've had decent results with using a solution of KCl.
35. ### Copper Impregnated anodes

i just recently acquired a few pieces of copper impregnated graphite. this stuff is supposed to have high wear resistance in EDM applications So i thought i would give it a shot in a chlorate cell. After a few minutes of operation my electrolyte which is a solution of KCL, turned blueish green...
36. ### Random Numbered .exe programs

yes Norton says it is a low risk trying to contact DNS server but when i scanned my pc it came up clean. I found all of the programs in the temp files folder. I am going to attempt to delete them
37. ### Random Numbered .exe programs

I have at least 30 of such processes running at one time
38. ### Random Numbered .exe programs

Hi i am having a little bit of a problem for some strange reason my computer is running random numbered .exe programs example: 361921.exe and each one is trying to contact the DNS server. Can anyone tell me what this is or how to fix it. I think it had something to do with the latest windows...
39. ### Potassium Chlorate

If you are trying to make chlorate i would go the electrolysis way. It might take a little longer and require a some work, but the results you get are a whole lot better thah boiling bleach. i a m actually working on a new cell design at the moment. If you are interested i could share my luck...
40. ### Nitration Reaction

I would like to know what happens when a nitrate is added to sulfuric acid. ex. KNO3 plus H2SO4 what does that yield.
41. ### Gaussina Elimination Help Needed

I think i got it now but if you got tips please share
42. ### Gaussina Elimination Help Needed

Homework Statement x+2y+6z=4 -3x+2y-z=-4 4x+2z=16 Homework Equations I am having trouble solving this equation since i was absent for notes I would appreciate an attempt to explain the process to me. The Attempt at a Solution I know the basics but if some one could show me...
43. ### Wire a potentiomete in to a circuit

its rated at 12v .15A. So how those this voltage regulator work exactly.
44. ### Wire a potentiomete in to a circuit

no they didnt i used a 9 volt battery no sparks no nothing until i got the right circuit and the motor turned on. But i am disapointed at how hard it is to get the right voltage i need a very specific voltage to achieve a maximum vortex which is around 5.6 volts. I've only been able to hit the...
45. ### Wire a potentiomete in to a circuit

thanks but i figured it out through trial and error
46. ### Wire a potentiomete in to a circuit

i need to know how to wire a potentiomete into a circuit. More specifically i am making a meagnetic stirrer and need to regulate voltage how would i wire the pot into the circuit.
47. ### Modified a computer power supply into a lab power supply

thanks that clears it up and sorry for my stupid mistake, but this is my fist time dealing with such electronics.
48. ### Modified a computer power supply into a lab power supply

so how exactly would you use a resistor to measure current. Would you get a 33A resistor and see if the voltage is what is supposed to be in this case it should be 5. Is that basically it
49. ### Modified a computer power supply into a lab power supply

yes i need to be able to measure up to at least 35A and digital meters only go up to ten. i was wondering what about the Ammeters used in cars can i use those.
50. ### Modified a computer power supply into a lab power supply

I recently modified a computer power supply into a lab power supply. I would like to check the amperes bieng output, but where can I get an ammeter? Or can i make one and how much does one cost. Heres a link to a pic of my PSU http://i106.photobucket.com/albums/m261/Squall_11/PSU002.jpg