Copper Definition and 497 Threads

Homework Statement a cylindrical bar of copper has a resistance of 0.02 ohms a) if the power of the bar is 10000 watts, what is the maximum current the bar can carry? b) the bar is now stretched to 3 times its original length, while the total volume of the bar remains constant. what is...

Hey all, I was wondering about a varied version of something. I know that if you run a magnet up and down a tightly coiled tube of copper, it creates an electric current through the wire. I also know the reverse, which is that if you passed a current through that wire, while it was wrapped...

Not just free electrons, ALL electrons. How strong would that be?

Homework Statement A copper calorimeter can with mass 0.100 kg contains 0.160 kg of water and 0.018 kg of ice in thermal equilibrium at atmospheric pressure. If 0.750 kg of lead at a temperature of 255^{o}C is dropped into the calorimeter can, what is the final temperature? Assume that no...

[SOLVED] Find the diameter of copper wire [FONT="Georgia"][SIZE="3"]Homework Statement Find the diameter of copper wire which has the same resistance as an aluminum wire of equal length and diameter 1.2mm. The reactivities of copper and aluminum at room temperature are 1.7x10^-8Ωm and...

[SOLVED] Electromagnetic induction Homework Statement You are given the following apparatus: copper ring, battery, variable resistor, lengths of insulated copper wire with connecting terminals at each end. Describe, how you would use all of this apparatus to induce a current in the copper...

Homework Statement I'm supposed to calculate the youngs modulus of a 2 meter length of copper wire. Homework Equations None The Attempt at a Solution for 30SWG i get 26GPa for 38 i get 3.1 GPa and for 24 i get 49 GPa Youngs modulus of copper is meant to be ~100GPa (from wiki)...

I’ve learned that copper wire is not generally used in a potentiometer. Is there any specific reason for this?

[SOLVED] Hookes law equation for all gauges of copper wire Homework Statement For my coursework I'm trying to find an equation using hookes law that works with all gauges of copper wire, i know that this means i will have to change the hookes law equation from F=ke to F=ake (a is not the area...

Question Details: In the figure the top wire is 1.1 -diameter copper wire and is suspended in air due to the two magnetic forces from the bottom two wires. The current is 50 in each of the two bottom wires. Calculate the required current flow in the suspended wire. i have been working...

Homework Statement A copper penny falls on a path that takes it between the poles of a magnet. Does it hit the ground going faster, slower, or at the same speed. The Attempt at a Solution Clearly the penny undergoes a change in magnetic flux. Since it receives a change in magnetic flux...

Homework Statement Calculate the reflection coefficient of copper for radio waves at frequency 50Ghz and yellow light (wavelength = 0.6 micrometers) Homework Equations Reflection coefficient: R = E(r)^2/E(I)^2 = (1-n/1+n)^2 Where E(r) is the electric intensity of the reflected wave...

Just looking through some old papers and found a problem that I don't know how to solve. Two identical 1.0-kilogram blocks of copper metal, one initially at a temp OC and the other initially at a temp of 100C are enclosed in a perfectly insulating container. The two blocks are initially...

Hi all, Biologist posting here. We have a thermal gradient that doesn't seem very stable. Right now, our setup is the following: hot water runs through one aluminum bar and cold water runs through another. the two bars are about 25cm apart. There is a thin aluminum plate resting on the...

Hey all, I have a pretty straightforward question about electron mobility in metals. We are given the length of a copper wire, it's radius, the current flowing through it, voltage drop across it, and the proportion of free electrons to copper atoms. I've found the current density...

Homework Statement Two 10-cm-diameter metal plates are 1.0 cm apart. They are charged to +/-12.5 nC. They are suddenly connected together by a 0.224-mm-diameter copper wire stretched taut from the center of one plate to the center of the other. A)What is the maximum current in the wire...

I'm trying to understand a bit more about high temperature superconductors. I'm familiar with BCS theory and a little bit about high temp superconductors, but I'm still confused about a bunch of stuff Why exactly is copper oxide used in high temperature superconductors? Why is this specific...

Strontium Chloride + Copper (II) Sulphate Pentahydrate --> ? Well, I did a lab in class a few days ago, where we were to react Strontium Chloride with Copper (II) Sulphate Pentahydrate, and determine what the precipitate formed was. Here's how the lab worked. We took 2.00g samples of each...

[SOLVED] Chem Lab Help! My AP chem class did an experiment where we started with 0.500 grams of copper and we ended up with 0.525 grams of copper after the experiment. The experiment consisted of us sending copper through different reactions to observe the effects of a series of reactions on...

Calculate the force required to pull a copper ball of radius 3.00 cm upward through a fluid at the constant speed 9.00 cm/s. Take the drag force to be proportional to the speed, with proportionality constant 0.950 kg/s. Ignore the buoyant force. For this question, do I have to find the mass of...

Okey, I have a problem now. I´m suposed to sketch a graf of how long range on a copper wire some different speeds have ex 256 kbit/s etc. I have 225 channels of each 4kHz and it can transfer 4000 symbols/sec. The effect on each channel is 0.1mW and the noise is -100dBm. The signal is...

Why do they say that copper wires are more conductor than aluminium wires?

Hi there! Can anyone help me with a problem. I did an experiment at school trying to measure the Young's modulus of a copper wire. We attached one end of the copper wire to a clamp and then tied on weights of 100g at a time to the other end so that a force can be applied to the copper wire...

A piece of copper wire has a resistance per unit length of 6.40e-3 ohm/m. The wire is wound into a thin, flat coil of many turns that has a radius of 0.190 m. The ends of the wire are connected to a 12.0 V battery. Find the magnetic field strength at the center of the coil. R/L = 6.40e-3...

I have a copper coin with a hole in the centre. The hole is a circle. If the coin is heated, the metal will expand towards all directions in and out, so the radius of the circle will be decreased. Correct?

Hello there I'm currently working on an EM device that should be able to measure the humidity in the ground. I cannot give too many details, but let's consider the following issue: I have a copper closed loop in which I send some current to generate a magnetic field. But there are some EM...

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...

Hi All, my friend has a big chunk of Copper Iridium metal. It attracts all non-metals like paper, wood etc and reduces it to powder. It is not a magnet because it does not attract iron. Can someone please explain this phenomenon ? Please forgive me if I am in the wrong forum. I am totally...

A copper pipe has an inside diameter of 6.720 cm and an outside diameter of 8.000 cm. What length of this copper pipe will have a resistance of 8.05 × 10-3 W? so i am using the equation R=rho(L/A) A=pi(d2-d1)^2/4 which is 1.29E-4 m and for copper rho is 1.7E-8 so...

please help me solve this... fermi energy of copper is 7eV. what is the fermi momentum of an electron in copper? what is the de Broglie wavelength of the electron? what is the fermi velocity?/// please help/////:cry:

A cylindrical aluminum pipe of length 1.36 m has an inner radius of 1.80 10-3 m and an outer radius of 3.00 10-3 m. The interior of the pipe is completely filled with copper. What is the resistance of this unit? (Hint: Imagine that the pipe is connected between the terminals of a battery and...

Homework Statement A 85.0 g hollow copper cylinder is 70.0 cm long and has an inner diameter of 1.0 cm. The current density along the length of the cylinder is 1.20×10^5 A/m^2. What is the current in the cylinder? Homework Equations possibly J = I/A where J is the current density The...

Hello All, Is there a way to predict the speed at which an electrical potential travels through a piece of copper wire? I know that the electrons themselves move very slowly (at the drift velocity), but how about the voltage potential itself? Are there any nifty equations out there to...

A piece of stiff copper wire hangs from a metal between the jaws of a u-shaped magnet and its free end dips into a pool of mercury. Mercury is connected to a positive terminal. piece of stiff wire will move: A towards the south pole B towards the north pole C to the right towards the support...

Two days ago in my physics class, one of my friends asked me a question: "There are 2 identical circular coils with radius 'r', length 'l' and 'n' no. of turns placed with their axes lying on a straight line, and current is let to pass through them so that mutual induction is observed.What...

If I have a sheet of copper, how can i calculate its resistance? do i just take the surface area of the thin side and compare it on an AWG chart?

Hello, say you have a cylindrical magnet magnetized through thickness (not radially) and you drop it through a copper tube. It will slow down. Is there an opposite force on the tube? If you were to hold the tube in your hand and drop the magnet inside, would the tube feel heavier?

Hello: I am having trouble starting this problem. "20.0 m long copper wire, 2.30 mm in diameter including insulation, is tightly wrapped in a single layer with adjacent coils touching, to form a solenoid of diameter 2.50 cm. What is the field at the center when the current in the wire is 26.0...

I'm really stuck on this one problem: "A small but measurable current of 4.20E-10 A exists in a copper wire whose diameter is 0.02 cm. Calculate the electron drift speed (in meters/second)." Source: Serway and Jewett I know that: I = 4.20E-10 A n = 8960 kg/m^3 q = 1.6E-19 C d = 2E-4...

I have a question. Assuming I have oil at 80 degrees in a copper calorimetry cup , will the heat loss by thermal radiation be very high and will it affect my values? I am thinking that it would not and that it would be negligible. But i do not know why. I heard somewhere that it would be...

Hey, this is a great 1 minute long video showing you how to make a homopolar motor using just one AA batter, a copper wire and a magnet. ENJOY! http://www.spikedhumor.com/articles/90173/Homopolar_Motor.html

Can someone please verify my results? and help me in one-2 questions? I did this lab in school today and had some problems filling in the table that followed. In the lab, we took some Copper Chloride and mixed it dionized water. Then we added in an iron nail and waited for about 20 mins. After...

Homework Statement 7.80 g of copper (II) sulfate pentahydrate (CuSO4*5H2O) were dissolved in a beaker of 50 mL of water and heated slowly. 2.00 g of iron filings were added to the solution, and then the mixture was allowed to cool. The supernate was decanted, and the contents of the beaker...

I put a copper pipe in a tank of water with dissolved iron in it and applied an electric current somthing like 6 volts at 1.5 amp and the pipe was hooked up to the positive terminal. After a couple of days some tourquise or pale green substance formed, i scraped this off and there was a copper...

in a recent chemistry experiment at school, two voltaic (galvanic) cells were set up with the same solutions in either beaker (one being Copper Sulfate, and the other was another metal solution) anyway, one had a potassium nitrate salt bridge, the other a copper wire salt bridge... sooooooooooo...

"Generation" of gold, silver, copper elements Since gold, and silver, and copper are all elements, I am a little confused - are they generated, or is there already only so much of each in the Earth, period? I know I found some data on Wikipedia that indicated that the various elements can be...

Okay, here is the problem: If the elastic limit of copper is 1.50E8 N/m2, determine the minimum diameter a copper wire can have under a load of 10.5 kg if its elastic limit is not to be exceeded. Obviously I am looking for d in this problem. I am given the downward force (102.9 N = ma); A =...

Hello, In a lab experiment, we filled 2 wells of a culture plate, one of them had 1.0 M CuSO4 and a piece of zinc metal, and the other well had 1.0 M ZnSO4 and a piece of copper metal. My question is: Which well has the reduced form of zinc and the oxidized form of copper? I know that...

G'day Forum, Struggling with the old materials science. Can someone please help me with the processes involved in modifying the properties of copper. I read that generally it doesn't respond to heat treatment.. is that true? Something bout cold working and hot working? what's the effect...

can YBCO be prepared in lab.?:biggrin: :approve: