Copper Definition and 513 Threads

I've been wrestling with something for a bit. I have one pound of copper (99%) in cube-form. Roughly 1.5 inches on a side. It's essentially a paperweight. Are those dimensions in the ballpark for relatively pure copper?

So basically, I‘ve always been told that solar cells work because of the PN-junction that exists between two doped materials. Then I‘d like to ask, how do solar cells work that use cuprous oxide - copper electrodes. The cuprous oxide acts as an semiconductor I guess? But It isn‘t doped, and the...

The answer I am getting is A but the answer given is D. I don't know why D because this is what I did. First I opened the alkene and then added OH on the less substituted carbon( Markonikov addition) and we know that Cu, Heat turns 3° alcohol to alkene so then I got an alkene. Did I do something...

I see different growlers and the one that seems the best uses 28 gauge copper wire X 2800 turns hooked to 120 volts AC does this sound right? I think this can be figured out using ohms law to so the windings do not get hot when AC is applied.

1) I have a "choke" with many copper windings on a soft iron core. I connect it to the 12V secondary of a mains transformer. I measure the voltage of the choke with a multimeter. What is the value and why? 2) I want to light up a 6V filament lamp. My supply is a 12V from a step down...

Q=m.c.DeltaT, is one approach which could possibly give the relation between Power vs Time. Is it correct ?

Can CuCl and Me6TREN form radicals? Reaction is at room temp and in water (not buffered)

Electrons have a magnetic dipole moment. If a permanent magnet was held against one end of a copper rod, the delocalised electrons close to the magnet would be attracted and concentrate around the magnetic pole. This should result in the creation of a weak electret because of the uneven...

Hi there, I have been trying to make iron oxide through electrolysis, I am using salt water as the electrolyte and an old alloyed steel (I am assuming iron and carbon) square pipe as the anode and a Rebar cathode. Unfortunately the beaker gets filled with this dark bluey color and when...

[Mentor Note: Two thread starts merged into one] I need to remove the Aluminium heat fins from a CPU heat extange lined around some copper water heat pipes. I could use a saw, cnc or grinder to remove them, but it seems that this way could be cleaner, and less probable to ruin the heat pipes...

a. The resistance thermometer bridge circuit shown in FIGURE 1 has a designed maximum temperature of 200°C, ignoring the effects of connecting wire resistance. If the connecting loop is 250 m determine the smallest gauge (swg) of copper wire which must be used if the indicated maximum...

I am working with HS students on measuring Current Gradients in Copper for their science project " Current Gradients in the human body during surgical cauterization". Next year I was thing of putting a thin sheet of Copper over strong magnets and using the Voltage gradient to draw the Current...

(Bloomberg) -- The warnings keep getting louder: the world is hurtling toward a desperate shortage of copper. Humans are more dependent than ever on a metal we’ve used for 10,000 years; new deposits are drying up, and the type of breakthrough technologies that transformed other commodities have...

When I use Ohm's law and other related equations to calculate the heating losses in a generator I get the power output of the generator. I assume I'm using the equations wrong, and I was hoping that someone could help set me strait. I think what I would like to know is what determines the...

Common sense: walking on road, there is traction between shoes & earth. I'm wondering: same thing for electric current's electrons & copper wire?

Inside a electric generator. To produce the most electricity catching the greatest number of electrons. Instead of spinning a magnet in front of a copper loop or spinning a copper loop between 2 magnet poles my thinking is flat copper sheets would have more surface area on a single magnetic...

What happens at the point all the copper moves out of solution and onto electrode during electrolysis of copper sulfate? Responding with anything other than an answer with an explanation is not wanted. Just an fyi, i learn by people showing me the answer and explaining why they think the...

I do not fully understand why a falling neodymium magnet is decelerated in a vertical copper pipe. It is usually explained by Lenz's law, two induced currents generate an upward force that counteracts the force of gravity. (link) However, I assume this upward force has to be generated by the...

I thought of few scenarios and they ended up as follows: The ring must have an induced current. Due to the symmetry of the ring, if one part of the ring feels a force, the part of the ring radially opposite this part will feel a force opposite in direction, since the current will be opposite in...

These videos show an electroless Cu deposition process onto a printed circuit board. I don't care about actually making a PCB, so the other steps such as PCB drilling, photolithography and electroplating thicker Cu aren't relevant. I'm only interested in the steps of electroless Cu...

i don't understand the answer: Nichrome has a higher resistance than copper wire. There is a greater potential difference across the nichrome than the copper wire. From ,the resistance of nichrome is low enough such that there is significant power output. ^ i feel like the bold parts contradict...

A copper wire contains 3.0 *10 ^ 22 number of charges on 1 meter wire. What speed do the electrons move when there is 2 A current in the wire. t=q/t=3,20*10^3 C/ 2.0 A = 1,5*10^22 s v= 1m/1,5*10^3s= 6,6*10^-4 m/s

I have an AC brush motor it has 12 slots where copper wires go and 24 copper bars, if you take 12 wires and go in a slot and come out at different slot and as you go around you filled all the slots now you have 24 ends 2 wires out of each slot which you connect to the 24 copper bars. Heres the...

Here I'm going to show all that I've understood - 1. 2. 3. What I've attempted - L = Lo (1+ α * ẟT) ẟT = 150°C - 15°C = 135°C (Steel) L = ẟL (1 + 11 * 10^-6 * 135) (Copper) L = ẟL (1 + 17 * 10^-6 * 135) This doesn't get me anywhere, obviously. Am I supposed to understand from the...

Hi Folks, I'm 70, so I often confuse myself! Ha ! My question is: Do materials both absorb and release heat equally? So when I evaluate different materials for thermo efficiency, does a copper pipe's surface absorb solar heat at the same rate it gives off heat? My question is specific to a...

I have attached the homework with some of the solution. I have ciuple of questions about it. For part b, what else I can say? I think the copper wite is ductile . Elastic and plastic behaviour have already been mentioned. I need to add another word to describe it. Can say it's hard ? Or...

I soaked the following school medallion in water with salt for 20 plus years in the attic and at that time I didn't know copper could corrode and make green oxides. I also didn't think about it much and just forgot about it. I brought it down just today. I read just a while ago that hot...

I am designing a board which will have relatively high current. The options are to use heavier copper (4 oz), use two layers (2 oz), or 4 layers (1 oz). Are there any benefits to using one configuration over the others?

I have a quantity of black, lustrous powder taken from inside a gas pipe. I want to know whether it's from copper pipe or from steel pipe. Is there a very simple test I can do? I'm not a chemist and have no specialist equipment.

If copper kills corona how come we've not spend money on putting it in hospital's etc ? How effective is it would silver be more effective?Our a combination of the both copper disc and a silver disc ?

https://www.smithsonianmag.com/science-nature/copper-virus-kill-180974655/ https://www.nih.gov/news-events/news-releases/new-coronavirus-stable-hours-surfaces The effect of copper seems to be independently verified. One should continue to use hand sanitizer and wear a protective face...

The magnet being used % magnet dimensions [m] d = .0127; r = .00238; %mass of magnet [kg] m_w = .0017; % other constants u_0 = 1.26E-6; % permeability of free space constant T m/A g = 9.81; % gravitational constant in/s^2 %coil properties [22 gauge wire] [m] a = .00635; %radius w =...

The shapes of the anodic and cathodic Tafel curves are different. What does it mean? Does it mean that the electrodeposition of the copper onto a surface of an electrode is uneven? If yes, I am also thinking that this has something to do with the macrothrowing power? Since it was done in an...

In my search, I have been looking for any data that might explain the RF resistance from 3 to 30 MHz range of the two basic types of copper oxides that form on the outside of bare copper wire. I believe these oxides become semiconductors and have large range of impedances. Due to the nature...

I have a copper cylinder that is at 0C, how much time will be needed for it to equilibrate with 10kg of water at 75C? Copper cylinder: Mass: 105.7 g Specific heat: 0.385 J/gC Initial Temp: 0C Final Temp: 75C ish SA: 25 cm^2 Water: Mass: 10000g Specific heat: 4.184 J/gC Initial Temp: 75C...

Homework Statement: Verify the claim of Section 7.2 that the electrons of a metal collide with the surface at a rate of about 10^30 per second per square centimeter. Do this by estimating the collision frequency of electrons in a 1.00-cm cube of copper metal with one face of the cube surface...

Summary: Insulated copper wires (not plated) inexplicably turned into gray powder. Wires are intact between affected spots. This is a piece of common red/black loudspeaker cable, with PVC insulation, pulled from service after about 18 months from installation. It was used to feed a small...

I tried to write down the equation of heat exchanged: ##Q_{Cu}=m_{cu}*c_{cu}*(T_f-T_0)## for the pot and ##T_f## is my unknown. ##Q_{H2O}=m_{H2O}*c_{H2O}*(T_e-T_{H2O})## where ##T_e=100 °C## is the temperature of vaporization of the water. But ##Q_{H2O}## is not all the exchanged heat by the...

What i did is: ##R=\rho\frac{l}{\Sigma}=\rho\frac{l}{d_2^2\pi-d_1^2\pi}## The problem is that I don't have ##\rho##. Is there a way to find ##R## without knowing it? Many thanks.

When soldering a brass fitting (e.g. https://www.pexuniverse.com/1-pex-x-3-4-pex-brass-pex-copper-fitting-adapter-lead-free-brass ) to copper (e.g. a 3/4 inch copper coupling) I think there is a danger that copper gets hot enough to melt the solder, but the brass fitting (being more massive)...

I am not sure where to put this but anyways, maybe someone here has had the experience and can tell me more about what important things would be necessary to do this. I am looking forward to making some electrical contacts that will have to survive a mercury environment in a sealed inert...

Hi all, so I had this problem and on the exam and I got a solution but I had an mass-term in there which wasn't given. I used Farraday's Law of Induction to get the Voltage induced. Then I used ##rho* \frac{A}{4a} ## for the resistance and divided the Voltage by that to get the current. I then...

Hi, A question has arisen an a hifi forum (sorry) that cables can be directional. I dispute this, as the proposed mechanism is diodes in the crystal structure etc. or the drawing process to crate the strands. Assume that it is 99.9% pure copper (CW004A (was C101)) and forms part of a cable with...

Hi, second problem in one evening, I'm sorry! But I'm also not quite sure if I did this one right. I had thought I need lenz's law but there is no current before entering the field so I just use the induced Voltage? My approach: ## V = \frac {B*A}{t} ## ## IR = \frac {B*A}{t} ## and ## A = v*t...

Relative DC permeability of copper is 1. Conductors are considered dispersive and therefore the permeability should change with frequency. Where can I find data or how can I calculate permeability of copper in Ghz frequency range?

Tried to find the resultant force, but I can't see how the magnetic field affects. I used Faraday's law to find the the diferece of potentials in the plate Wich should be B.d.v, where v is the vertical velocity of plate, but there were not given the resistance or resistivity to relate with the...

"The surface of copper naturally oxidises, forming a thin hard layer on the surface which normally prevents further oxidation. " I've seen this in a book, higher level oxygen on busbar, means lower the heat and get away with ease, Doesn't it? So, Can I say a thin hard layer musn't be used?