Coaxial Definition and 188 Threads

I'm designing a test fixture and need a compact coaxial electric motor. The motor drives two counter rotating fans with tip speeds up to 650 fps (desired), 500 fps (required). The fan diameter has not been selected, but is between 2 to 3 ft. Initial estimates suggest that the total fan...

Hi everyone I have a problem to solve, I already simulated it with FEMM, but I wonder if it is possible to find an analytical solution. Let's say that there's a small coil (100 turns) around a pipe (2in diameter), the pipe is filled with air. This pipe is located inside a bigger pipe...

This is for an electromagnetic theory class. Homework Statement Prompt can be seen here Homework Equations J = I/A, J = σE, V = Ed, C = εA/d The Attempt at a Solution I'm having trouble mostly with parts i and ii, as the rest are fairly simple to acquire after figuring out those two...

Hello all. Let me start with my main question and then provide a bit more background. I just noticed that an unused coaxial cable outlet in my apartment is periodically producing a faint but very noticeable buzzing sound. It seems to come and go, flickering on and off sometimes and...

Is there a coaxial digital to analog converter that only decodes the digital signal into multiple signals for the channels and then converts the digital signals into analog signals but does not serve as a digital tuner? Because most coaxial digital to analog converters do not decode the...

Hey all, Between two devices, I will need to have a coaxial line (with SMA connections on either end) connecting them. The operating frequency of the signal I am propagating is approximately 125 MHz. With this said, the wavelength (assuming ideal) is 2.4 meters. I have heard from numerous...

How does current flow in a coaxial cable in each of the following cases : 1. When the cable is connected to a DC voltage source. 2. When the cable is connected to an AC voltage source 3. When the outer metallic shield is connected to ground and DC and Ac sources are connected separately I...

Hi, I am trying to model electrical equivalent of a coaxial cable. The data I have is 1. Conductor resistance 2. Insulator resistance 3. Partial discharge 4. Insulation Thickness 5. Overall diameter Actually I planned to use an equivalent circuit that has series connection of...

Homework Statement An annular sheet, of thickness t=1mm and resistivity ρ=0.5Ωm, connects the inner and outer conductors of an air spaced coaxial transmission line at a point on the line. A low-frequency signal is fed into one end of the line and the other is terminated by its characteristic...

Homework Statement I am given the following problem: http://forum.allaboutcircuits.com/attachment.php?attachmentid=35938&d=1320027350 Homework Equations The Attempt at a Solution My known equations and attempt to the problem...

Homework Statement Hi, I'm having issues with a question about a coaxial cable. This is the question: A coaxial cable consists of a long straight cylindrical wire of radius R1, surrounded by a coaxial cylindrical shell of radius R2. For a situation where the inner cylinder carries...

Homework Statement I have attached the question as a pdf. Homework Equations I'm thinking that we take the line integral of voltage to get electric field. But I'm not sure how to proceed from here. Is the line integral from a to b? Also, how do I get the charge density having found...

Just out of interest I was wondering and couldn't work out... Why are (even high-end) speaker cables not coaxial? We always use a coaxial cable in the lab to get rid of the noise on our measurements. I figure that 50/75 ohm standard coax would create an impedance mismatch with the typically...

One of the textbooks I've stumbled across states that the radial resistance of a coaxial cable ( current running from inner cylinder to outer cylinder via silicon in between) is given byR = [resistivity * natural log of (b/a)] / [2*pi()*(length of cable)] where b is the outer radii and a is the...

Homework Statement An alternating current I = I_0 \cos(\omega t) flows down a long straight wire and returns along a coaxial tube of radius a. By constructing an appropriate Amperian loop or otherwise, and assuming that the induced electric field E goes to zero as the distance from the...

On a coaxial transmission line is there AC current running through the center wire? And this AC current produces EM radiation that bounces down the wave guide. So is the purpose of this transmission line to send the signal via radio waves. And is this how cable tv works, are radio waves being...

I think I solved this problem correctly, I just want to check because it's an interesting problem, and it's from a past exam. Homework Statement A coaxial cable consists of an inner solid conductor of radius r_1, and and outer conducting cylindrical shell of inner radius r_2 and outer...

I'm having a tiny debate with someone over whether a 2nd coaxial rotor generates additional lift for a helicopter by itself or the helicopter has additional lift only due to the elimination of the tail rotor so 100% power goes to generating lift? My theory is that it does not generate...

Homework Statement A long coaxial cable consists of an inner cylindrical conductor with radius a and an outer coaxial cylinder with inner radius b and outer radius c. The outer cylinder is mounted on insulating supports and has no net charge. The inner cylinder has a uniform positive charge per...

Homework Statement The problem asks us to find the magnetic field inside a coaxial conductor that consists of an aluminum wire of radius r1 surrounded by a cylindrical aluminum shell of inner radius r2 and outer radius r3. I know how to do this, but it also says that there is oil flowing...

Homework Statement So I'm doing a problem set and the question refers to a coaxial cable, I am told that the cable consists of an inner solid cable radius (R1), which is surrounded by a outer thin tube with radius (R2) , both have the same current though them but opposite direction. I have to...

Homework Statement A coaxial cable is made from concentric cylindrical conductors. The radius of the inner conductor is a and the outer comductor has inner radius b and outer radius d. Calculate the self inductance per unit length of the cable. You may assume that (b-a) >> a and (b-a) >>...

Homework Statement Consider two coaxial conducting cylinders with radii a and 3a and length L. The region a<r<2a is filled with a material of conductivity σ1, and the region 2a<r<3a has conductivity σ2. (Assume ε1=ε2=εo.) The inner cylinder is held at potential V0 and the outer cylinder at...

Homework Statement A wire with uniform charge density λ per unit length is bent into a ring of radius a and rotates with angular velocity ω about an axis through its centre and perpendicular to the plane of the ring. Find the magnetic field on the axis at a distance z from the ring...

Homework Statement A high voltage coaxial cable is used to supply power to an x-ray generator. The cable consists of an inner wire of radius r=1 mm and a thin hollow outer conductor of radius R= 10 mm. The inner wire and the outer shield have the same charge density per unit length of ...

1. A long coaxial cable consists of an inner cylindrical conductor with radius "a" and an outer coaxial cylinder with inner radius "b" and outer radius "c." The outer cylinder is mounded on insulating supports and has no net charge. The inner cylinder has a positive charge per unit length λ...

Homework Statement A coaxial cable consists of a long solid inner cylindrical conductor, radius a, and a thin outer cylindrical conductor of average radius b>a. Suppose the inner conductor has a line charge density of +lambda while the outer conductor has a uniformly distributed charge of...

A coaxial cable has a conductor lying at the centre of a thin walled cylindrical conductor. These conductors are separated by a plastic dielectric, and they carry equal current in opposite directions. The radii and current are given, and I must find the magnitude and direction of magnetic...

Homework Statement A coaxial cable has an inner core diameter 6mm and inner diameter of the outer sheath is 20mm. There are two layers of insulation between the conductors, the inner layer from a radius of 3mm to 9mm has relative permittivity of 8 while the outer layer from radius 9mm to...

Homework Statement Say we have an infinitely long wire with radius r1 with a linear charge density +u and we have a coaxial conducting cylinder with radius r2->r3 and a linear charge density of +2u. http://img573.imageshack.us/img573/3419/coaxialcable.png" Now the overall aim of the...

If a hypothetical flying car used turbo fans and/or co-axial rotors that were built into the structure, has a fairly boxy design and looked almost like a normal car (size, shape, curves, angles, design) what sort of performance could it get with today's technology? If it was hybrid electric...

Homework Statement Calculate the energy per unit length for two long coaxial cylindrical shells, neglecting end effects. The inner and outer cylinders have radii a and b, and linear charge densities λ and -λ, uniformly distributed on the surface, respectively. 2. The attempt at a solution...

Homework Statement Consider an 8mm diameter coaxial cable, which consists of a central conducting wire, and an outer cylindrical conducting braid. If a charge of +30mC is placed on the inner conductor, and a charge of -30mC is placed on the outer conducting braid, what will the electric field...

Physics 2 coaxial potential help! https://wug-s.physics.uiuc.edu/cgi/courses/shell/common/showme.pl?cc/DuPage/phys2112/summer/homework/Ch-22-E-Potential/IE_cylindersV/coax.gif The diagram above shows a coaxial cable. The inner conductor has radius a = 0.0025 m. The outer conductor is a...

If I have a long coaxial wire with open end and apply a short voltage pulse, that pulse begins propagating through it until it reaches the end. Then, it reflects back to where it came from. I understand that it behaves like a normal wave, maintaining its energy and bouncing when it reaches a...

Homework Statement Two long thin concentric perfectly conducting cylindrical shells of radii a and b (a<b) are connected together at one end by a resistor of resistance R, and at the other by a battery that establishes a potential difference V. Thus, a current I=V/R flows in opposite...

[b]1. Charge of uniform density 76nC/m^3 is distributed throughout a hollow cylindrical region formed by two coaxial cylindrical surfaces of radii 1.5 mm and 3.7 mm. Determine the magnitude of the electric field at a point which is 2.6 mm from the symmetry axis. I tried...

1. Homework Statement I just have a question concerning an unbalanced coaxial cable. By unbalanced, I mean that the inner and outer currents are not equal magnitudes of the opposite direction of each other. My homework problem has an inner current of +100[mA] and an outer current of 90[mA] in...

Homework Statement I just have a question concerning an unbalanced coaxial cable. By unbalanced, I mean that the inner and outer currents are not equal magnitudes of the opposite direction of each other. My homework problem has an inner current of +100[mA] and an outer current of 90[mA] in the...

Homework Statement A copper wire is surrounded by insulation, then a copper mesh, and then an outside insulation. Assume the current in the inner conductor is going into the page and an equal magnitude of current is flowing out of the page in the copper mesh outer conductor. a. Which...

Hi all, The situation is this: I need to calculate the self inductance of two solenoids wired in series, of equal radius and a given separation d. They are coaxial. The length h of each is known. Most double-solenoid references I found looked at the mutual inductance, and not the...

Homework Statement If I have two co axial conductors at V = 0 and the dielectric has a free charge density. Is that physically possible? Homework Equations No relevant equations The Attempt at a Solution I am not sure if you can have free charge density in a dielelctric when both conductors...

Homework Statement Type P241B coaxial cable has an inductance of 0.4 μH/m and a capacitance of 40 pF/m. The diagram below shows a 100 m length of this cable connected to a battery and switch at the sending end and a 50Ω resistor at the receiving end. (a) If S is closed, what initial current...

Homework Statement Consider a coaxial cable that consists of inner/outer conductors of radii a and b, and it is filled with electron cloud with volumetric charge density of ρv = Υ/ρ [C/m3] for a < ρ < b. If outer conductor is +Vo [V] more positive than inner conductor, find E field between...

Homework Statement Two infinite coaxial metal cylindrical tubes of radius a and b (a < b) are charged with charge per unit length (unit [C/m]) \lambda and -\lambda respectively. Calculate the electric field between the tubes (i.e. for a < r < b) Where \epsilon_{0} is the permittivity...

Homework Statement A coaxial cable of circular cross section has a compound dielectric. The inner conductor has an outside radius a , which is surrounded by a dielectric sheath of dielectric constant K_1 and of outer radius b . Next comes another dielectric sheath of dielectric constant...

Homework Statement A coaxial cable of length l, has a thin wall cylindrical inner conductor of radius a carrying current I. All current returns along the outer conductor whose inner radius is b. Assuming that the current flows only in a thin layer on each conductor, determine the magnitude...

Homework Statement If the outer conductor of a coaxial cable has radius 3.5 , what should be the radius of the inner conductor so that the inductance per unit length does not exceed 55 per meter? Homework Equations The Attempt at a Solution 1.385

Homework Statement Find the capacitance per unit length of three long coaxial metal tubes, with radii a < b < c . A wire connects the innermost and outermost tubes (radii a and c). Homework Equations The Attempt at a Solution I'm a little confused as to how I should set this...

One of my professors made an X-band cavity resonator by putting together, end to end, two X281A coaxial waveguide adapters (n-type) with cut center pins. It works pretty well - but I need some more information. Does anyone know where can I find some more information on this setup...