Wire Definition and 1000 Threads

For instance, a current through a wire makes a magnetic field around it, and the changing magnetic field creates an electrical field, which then creates a magnetic field, and so on. Are these fields pulling on the wire? If so, how exactly? Isn't every piece of the wire dx electrically neutral...

Need some help in understanding the current ratings of wires. I had asked about this in another thread, and learnt that power ratings of wires depend on numerous factors. To simplify things for me, I could successfully dig out the product datasheet from one of the notable companies in my country...

Two different projects require me to understand the behavior of a basic signal wire at 20-100 kHz and also at 1.7-2.1 MHz. So I tried to go to basics and take, as a starting model, a single real wire say 18 AWG of pure Cu to make it simple and understand the frequency dependent impedance...

My wire is 16 AWG (264 cores of 40 AWG) with 0.010 FEP Insulation. I have the insulation and the MJF nylon that it is touching melting! How much current would I need to have to get to these temperatures with this wire? This wire is inclosed inside the MJF nylon case, so figure for no air flow.

Homework Statement: circuits - terms Relevant Equations: - How exactly can the electric potential be constant between two points in a wire; (assuming that it is electron current); if the electron is moving from a region of high electric potential to a low electric potential because of the...

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.

A wire coinciding with the X-axis carries a current I1 in the direction of increasing x. A second wire is parallel to the Z-axis at a distance R, and carries a current I2 in the downward direction as indicated in the figure. The magnetic field at point P (0, 0, R) is: (options and diagram in photo)

Hello, I bought AC, so I need to connect a copper pipe and electrical wire from the indoor unit to the motor. Can I twist the connecting cable(electrical wire) with the connecting pipe(copper pipe)? Is it safe?

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

I proceeded as follows Current in sector ##d\theta=## is: $$dI=\int_{x=0}^{x=R}{\frac{I}{\pi R^2/2}\times\frac{d\theta}{2\pi}\times 2\pi x dx}$$ Field due to sector ##d\theta## is therefore $$dB=\int^{x=R}_{x=0}{\frac{\mu_○}{2\pi x}\times\frac{I}{\pi R^2/2}\times\frac{d\theta}{2\pi}\times 2\pi x...

TL;DR Summary: Finding the power loss in a wire of varying area - my problem is I don't know how to set up the integral Hopefully you can see in the diagram below that the area of the wire varies linearly with length. I know the equations for resistance and power loss and I can express the...

I have a question about a derivation I saw in the book "Heat and Thermodynamics" by Zemansky and Dittman. A "sufficiently complete" thermodynamic description of a wire is given in terms of only three coordinates 1. tension in the wire, ##\zeta## 2. length of the wire, ##L## 3. absolute...

Here is the question. I just wanted to confirm and see if I'm understanding the question clearly. For 3a) I said the first wire would have the magnetic field going in a counter clock wise direction and the second wire would have a magnetic field going in a clockwise direction using the right...

Hello, We need 20 meters of 12 Gauge electrical wire but don't have 12 Gauge wire. Can we use two 6 Gauge wires and twist the two ends of the wire together? Is it harmful to electronic appliances? for example, air conditioners [Mentor Note: original question restored; the OP will post a follow...

Suppose I have a current carrying wire that is 20 AWG copper. There is insulation on the copper wire that is rated for 200 degrees C. I have 500 meters of the wire wound into a coil. The coil takes up a total volume of 0.0001157 meters cubed (roughly 1000 turns). Suppose I run 3 amps of current...

TL;DR Summary: We purchased a 9v battery box and planned to wire it—in parallel—to 10 mini bulbs, assuming 10 bulbs drawing from the 9v would be more than enough voltage drop to not go up in smoke. We purchased a 9v battery box and planned to wire it—in a parallel circuit—to 10 mini bulbs...

Hello PhysicsForums! Here is my attempt at a solution for the problem stated above: Where m1 and m2 are the masses Where Ff1 and Ff2 are friction for each mass Where a1 and a2 is the resulting acceleration Where S is the fore of the wire (threadforce) Where FN is the normal force The answear...

Hi, I am not sure if I have calculated the task here correctly: Based on the drawing, I now assumed that the two resistors are connected in parallel. The total resistance can then be calculated as follows ##\frac{1}{R_T}=\frac{1}{R_1}+\frac{1}{R_2}##. Since the two wires are made of the same...

How should I calculate the angular momentum carried by a current carrying circular wire? Is it correct to consider the angular momentum of the electrons moving with drift velocity? Like ##L = n m_e v_{drift} r## where ##r## is radius of the loop, and ##n## is total number of electrons moving in...

I initially tried to solve this equation using work, but was stuck in a confusing integral that didn't make sense. I am almost sure that the utilization of energy is needed to solve this equation, but I have been flustered for the past three days at solving this.

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...

300 000km connect light bulb and battery. I would say 1sec is need from I turn on switch to light start lighting. This video say it is 1m/c...Is this video wrong? Do electron travels thorugh wire, if 300 000km wire is connected to bulb ,why electricitly travel through space only 1m??

I thought the answer is (B) because thinner wire means higher resistance and smaller current so smaller power dissipated in the wire, but the answer is (A) What is my mistake? Thanks

Hi, So I know I am to use Biot Savarts law dB= (my_0/4pi)* (I dl x (r-r')/|r-r'|^3 where r=0 because its in origo and r'=r'_c(r'_hat). This makes (r-r')= -r'_c(r'_hat) and |r-r'|^3= r_c^3. From previous questions, I have defined dl' as the infinitesimal displacement of r'(phi) when phi' is...

For this problem, The solution is However, I would like to understand how to solve this using Biot–Savart Law. So far my working is: ## \vec {dB} = \frac {\mu_0Ids\sin\theta} {4\pi r^2}## However, I'm not sure what to do about the ## r^2 ## since the wire is infinitely long. I am thinking...

For this problem, The solution is, However, why did they not use limits of integration for the integral in red? When I solved this, I used as limits of integration. I see that is not necessary since you get the same answer either way, but is there a deeper reason? Many thanks!

My thoughts were I could use mesh current analysis to derive equations for current hence power in each case in terms of ωC and R, set the equations for real power equal to each other and solve for R. While ωC are known I opted to leave them as letters thinking this might make life easier when...

I want to make my own multi-wire chamber for school, and I wonder what kind of effect different wires will have on the efficiency. After reading many papers containing research for wire chambers, I saw that all of them did tests with wires made of gold plated tungsten wires with a diameter of...

Planning a kitchen renovation. We've found a SIEMENS iQ700 glass downdraft extractor [model LD98WMM60B] that we'd love to use. It, of course, is only available in EUROPE. EAN code : 4242003907122 Connection rating : 300 W Fuse protection : 10 A Voltage : 220-240 V Frequency : 50; 60 Hz Plug...

Setting up the integral to find the flux that is giving me trouble. I know that I will have to break up this integral into 2 parts, the first part account for when the start of the loop is increasing in area, and another right when I pass the halfway mark of the loop and the area begins to...

Hi I'm doing my extended essay (like a research paper) for the IB and I'm having a bit of trouble with my setup and data process. The plan for my experiment goes something like this: I have a magnet wrapped in wire strapped to a battery and a superconductor in liquid nitrogen. After levitating...

Statement: The magnetic field around a straight wire carrying a current can be explained Relativistically by changing the inertial frame of reference to the frame of the moving electrons - i.e., a Lorentz contraction of the positive charges in the wire will give a denser concentration of the...

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

This question appeared in a university entrance exam.Basically, if magnetic flux passing through a surface of a loop changes over time ,only then e.m.f will be induced to that loop.But here only a straight line is used and there's no chance of forming any area.So by definition there's no chance...

I wanted to make a simple platinum electrode with a few cm of wire. But it is hard to get. Local (Australia) science equipment suppliers are now citing platinum wire as a drug precursor. I can't see how anyone uses platinum wire or salts as a drug to get high. I am puzzled, in any case it...

If you have 3 phase power and let's say line A & B = 10 amperes line B & C = 10 amperes line C & A = 10 amperes For the single line B. Since it's in both in the first and second lines, then B can experience 10 + 10 = 20 Amperes? Or is it 15 A or still 10 Ampere? Thank you.

The actual homework question is about finding the voltage of a tapered wire, one where the two ends are different sizes (1cm and 2cm in this case). I've been searching for an equation to do this simply by just plugging in the values I have and I came across this. Where is resistivity, h is...

Summary: Question about expectations related to electron flow and conductivity. Here's a question I have... imagine a scientist in a lab. In front of him there's a battery (with typical red/black +/- poles). Behind him is a normal light socket. Now, between the battery and the light socket...

Hi. (not a native English speaker, so apologies in advance for inadequate techical terms) 220V AC, Europe. There is a cable with 5 wires (2.5mm2 crosssection each) that I would like to cut and make a junction box in the attic to connect another cable to it, to get another outlet. The wires are...

To solve this problem, we need to evaluate the following integral: $$\epsilon = \int_{P}^{C} (\vec v \times \vec B) \vec dl$$ The main problem is, in fact, how do we arrive at it! I can't see why a Electric field arises at the configuration here. The magnetic field of the rotating sphere is...

I think the answer is that the elastic potential energy will be a 1/16th of the original value. This is my reasoning: 1) If the diameter doubles, the cross sectional area is 4 times the original value. (from A= πr2). 2) F= stress/area. Force (load is the same). If cross sectional area...

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If I'm correct then the maximum change in magnetic flux occurs when the semi circle crosses the point at which it's plane is parallel with the magnetic field and minimal when it crosses the point at which the magnetic flux is maximum ( perpendicular with the field). I'm having trouble writing a...

What I have done: (1) ##\Phi(\vec{B})=\int_{S}\vec{B}\cdot d\vec{S}=-\frac{N\mu_0 il}{2\pi}\int_{s=h}^{s=h+l}\frac{ds}{s}=-\frac{\mu_0iNl}{2\pi}\ln(\frac{h+l}{h})## so ##\mathcal{E}=-\frac{d\phi(\vec{B})}{dt}=-\frac{\mu_0iNl^2v}{2\pi h(h+l)}## so...

Can someone explain how there can be a radial magnetic field? I thought the magnetic field was always tangent to the circle using the right hand rule where you wrap your fingers around the current and point your thumb in the direction of the current.

We are dealing with extremelly thin (radius of order in mm) wires of gold at the project i am. It is necessary to plug these wires at a copper plataform. We have think two ways to do that: To weld it, or, to buy a plug that allow us to do that. SInce to weld it is the second option, we are...

I have a NanoVNA spectrum analyzer. I took a 1 meter 12 AWG solid copper wire and soldered one end of that to the center conductor of the SMA connector and did a sweep from 10 kHz to 1 Ghz looking at reflection. I have attached a photograph of the result. My hope is that someone can tell me...

Hi! I'm trying to understand electromagnetism. So I had a question: if we place a bar magnets on the low friction surface near vertical wire, then switch on the current, what will happen? As I been told they will align with the magnetic lines, and then nothing will happen. I also suggest that...

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...