Transmission Definition and 708 Threads

After looking at my notes and http://cnx.org/content/m16027/latest/" I have become utterly confused about Energy transmission in Waves. What? In a traveling wave KE=PE? If so, when a particle is at its max displacement, KE=PE=0 and so KE+PE=0 and yet then a particle is as its mean...

Homework Statement An electron with kinetic energy 5 eV (8.01E-19 J) passes through a 3 eV (4.806E-19 J) potential barrier. There are certain widths for this potential barrier in which the transmission probability will equal one hundred percent and the reflection probability will equal zero...

Hello Physicists, I am doing my final year of High School in Australia and our current topic is magnetism and related fields. Physics is my favorite subject after maths and I tend to query a lot of things. Here is my basic Idea: My basic instinct tells me that the orange wire must be...

hello forum, has anyone heard before about a Goubou wave and single wire transmission? I always thought that for a circuit to properly work two conductors were needed, the signal conductor and the return conductor, both in DC and AC... Is that true? thanks. fisico30

Hi, Power transmission over long distances from power plants to local power grids is often done over DC with relatively high voltages/tensions. The argument for this is that since, by Joule's law, power dissipation due to heat by a resistive element is given by I^2 * R, lowering the current...

In high speed digital designs, there is a series terminating resistor to match the output impedance of the driver IC with the transmission line on the PCB. Some think the purpose of this resistor is to decrease the drive of the IC. How do I convince them its not to decrease the (current) drive...

I'm a bit confused about why power is transmitted at high voltage for transmission over long distances. This is generally explained as reducing Joule losses, P = I^2 R, and we minimize the current by maximizing the voltage. However, a trivial re-arrangement using Ohm's law gives also P = V^2...

Find the inductance per unit length of parallel plate tx line width = w and space =d between the two plates. w>>d. My question is whether the total inductance is twice the calculate inductance because total inductance is the sum of inductance of the top and the bottom plate. But it seems all...

The Klein Paradox is the name given to the following prediction of Klein Gordon's equations. If you send a current of electrons against a potential barrier of height V such that the energy of the incident electrons is less then V - m, you should observe a current of positrons coming out of the...

Homework Statement I have this equation: T=(1+\frac{U_{0}^{2}}{4E(U_{0}-E)}sinh^{2}(2 \alpha L))^{-1} Where α is given by: \alpha = \sqrt{ \frac{2m(U_{0}-E)}{\hbar^{2}}} I have to show that in the limit αL>>1 my equation is approximately given by...

An electron having total energy E=4.46 eV approaches a rectangular energy barrier with U=5.02 eV and L=949 pm. Calculate this probability, which is the transmission coefficient. I thought this would be an easy one, given that T=e-2GL and G=\sqrt{\frac{2m(U-E)}{H}} where H is the...

Today in my high school physics class, we were shown that object 1 vibrating at object 2's natural frequency, can cause object 2 to vibrate. So since you are transferring energy, i was wondering if its possible to use ultrasonic or infrasonic sound waves to vibrate a magnet, causing a current to...

Homework Statement Consider the potential V=V_0 d[\delta(x-a)+\delta(x-a)]. Find the transmission probability of the potential for a particle of mass m and wave number \sqrt{\frac{2mE}{\hbar^2}} incident on the potential. Discuss the behavior when ka~\pi/2. Homework Equations Schrodinger's...

Hello all, This question might be at the same time both general and very specific. Admittedly, it has been over 10 years since I really thought about circuit analysis, but I hope I might get some help here! So, thanks in advance! I will ask a few questions here to make the presentation...

Homework Statement Find the transmission coefficient for the potential V(x)=-\alpha\left[\delta\left(x+a\right)+\delta\left(x-a\right)\right], where alpha and a are positive constants. Homework Equations T \equiv \frac{\left|F\right|^{2}}{\left|A\right|^{2}} The Attempt at a Solution...

I need help with this tutorial question I cannot solve! a consumer demands 50kW at an effective voltage of 230V. supply system can be represented by a 0.1ohm resistance. Find the transmission losses in the event of the load being supplied with a power factor of 0.6 lagging. I know the...

Homework Statement A belt drive transmits 56kW from the driver pulley to the driven pulley. If 2.5kW is lost in belt friction, calculate: 1. kW's supplied by driver pulley 2. efficiency of the belt drive expressed as a percentage. Homework Equations %Efficiency = (power...

Say you had a lossless transmission line that consists of an ideal source, a 50 ohm impedance, a 100 ohm impedance, and a 100 ohm terminator. The material is the same. You send a pulse down the line. When the pulse hits the impedance mismatch, you get a smaller reflection back, and a pulse...

Homework Statement The complex index of refraction of silver at 532 nm is \tilde{n} = 0.13 + 3.19i. What is the transmission for this light through a layer of silver that is one wavelength (in the medium) thick? In this problem, don't worry about reflections from the boundaries, just consider...

I want to confirm that the TEM wave is actually travel inside the dielectric between the two plates of the parallel plate transmission line. So even though surface current and surface charge appeared on the surface of the conductor plates as the consequence of the boundary conditions between the...

Homework Statement In manipulating transmission spectrum data from GaAs and InP I'm told to "Look up the refractive indices of GaAs and InP in the region of  = 1.0 micron, and use these to correct your experimental data for reflective losses and plot the corrected transmission T’ in...

I have been using etap 7.5 demo and have been trying to model an HVDC link connected to 2 buses and conduct a load flow analysis (there is also a generator in swing mode attached to one bus and a normal transmission line connecting the two buses to satisfy the simulation requirements), but it...

Is it physically conceivable the possibility of transmitting electricity between spatially separated objects (e.g. a few meters) in a wireless way?

There's this internet rumor I came across where marconi heard a transmission before transmitters were invented? Some theorists (lets go easy on them please) beleive that - Marconi wasn't the first to invent the radio - but one of the few civilian inventors to come across it. Does...

Homework Statement A frequency band from 76 MHz to 86 MHz is available for wireless transmission. Design a frequency division multiplexing system with 2 MHz wide channels and 2 MHz guard bands (assume that guard bands aren’t necessary at the lower and upper ends of the band). Indicate...

Perhaps sb is able to point in the right direction. The task is to calculate the value of the receivig end volatge, for a load of 10 MW at 0.9 pf taken from 66 kV substation. First I calculated the transmission line impedance Zlinebase=(Vbase^2)/MVAbase Zlinebase=132^2/100=174.24Ohm Zlinepu=...

Homework Statement i was wondering why would high-voltage transmission cables disturb a car's radio reception with static?Homework Equations The Attempt at a Solution Could it be because of the frequency of the voltage? Or something in terms of frequency? Thanks :smile:

I want to verify the theory of TEM mode tx lines how the signal travel. Please correct me if I am wrong. This mainly refer to stripline, microstrip( assume TEM) etc. 1) The signal is transmited as EM wave through the dielectric between the two lines, not actually current through the...

hi there. can anybody advise with this one please? a short 3 phase 11kv line delivers a load of 4.1 mw,2.6 mvar lag if the series impedance of the line is (7.2 +j12.1 ) calculate the sending end voltage and load angle. the thing which is confusing me is the 2.6mvar lag bit,i know i...

wireless power transmission: a new method I was having an idea that if i can somehow reverse the operation of Voltage controlled oscillator i.e if i can make the circuit to input high frequency(e.g radio wave) and give output in proportional amplitude(or voltage) then if i can glow even a small...

Homework Statement Estimate the transmission of light with \lambda=1\mu m that is transmitted through 20nm thick gold film at 77k where The DC conductivity: \sigma_{DC}=2*10^8 \Omega^{-1} m^{-1}) The carrier density: n=5.9*10^28 m^{-3}) and the plasmon frequency...

I have two questions about Tx lines 1. Can we think of the Tx line in terms of just LC ladder. If yes, why can't this be thought of as a LC filter. In that case, the tx line would be a low pass filter. Increasing C would make the cut off freq even lower. 2. If I don't terminate at the load...

Why do reflections occur in transmission lines. Why does the wave travel back from the load?

I am building an algae scrubber for a reef tank and am trying to decide what material transmitts the largest percentage of PAR. My choices are to place the lights an inch or so from the algae with a clear shield, or move the lights at least 12" away to avoid salt spray/creep. I don't know a lot...

"Transmission lines are specialized cables and other media designed to carry alternating current and electromagnetic waves of high frequency (radio frequency or higher), high enough that its wave nature must be taken into account. Transmission lines are used for purposes such as connecting...

In order for us to see something, the light photon needs to be reflected, not absorbed or transmitted? Then is it that the same frequency of visible light keeps falling on something, an apple is always red in white light, why does it reflect red?

The high-speed (USB 2.0) protocol is capable of 480 Mbit/s. How can I send data at these speeds!? This seems like a simple question, but I cannot seem to find a simple answer. Cheers, JoAr

I would like to know if Transposition on Transmission Lines could affect the basis and the way the power system is evaluated to set up the protection for the Transmission line? as compared to the non-transposed Transmission Lines. Thanks in advance, Regards,

If a source which has internal impedance 20 ohms is connected to multiple transmission lines of impedance somewhat equal to 20 ohms, which vary in length(maybe from 1" thru 8"). How do I analyze the reflections/draw the bounce diagrams. According to a patent -...

Hi, I'm learning something on circuit QED, which has a part called transmission line resonator (TLR). It plays the role of a cavity. However, I don't get how it works that way. Can anyone give some help ? Thanks in advance !

Homework Statement A typical power station produces 1000MW of electrical energy. Seven percent of the power is lost in a 500kV transmission line. Whats the lines resistance? Homework Equations P=I2R The Attempt at a Solution Thought this problem was simple but I keep getting it wrong. P=I2R...

Hi, I've been mulling over an idea (you know how it is, just to keep the grey matter ticking) on how to build a device for tracking...well anything... from hunting dogs to humans. The device would include a GPS (lat, long, altitude, vert & horz accuracy, UTC time) to give bearing over time...

Homework Statement A 69 kW single-phase load with a power factor of 0.68 lagging is fed by a long cable with an impedance of 0.011+j0.005 Ω per phase. The voltage across the load is 230 V RMS. Calculate the heat loss in the cable in Watt [W]. Homework Equations The Attempt at a...

Homework Statement This is not a HW problem. Just refreshing Tx line theory(reflections). I have a pulse of 3.3v, period 36nsecs. (Ton=18ns, Toff=18ns) with a source impedance of 50 ohms, connected to a tx line of impedance 50 ohms. The load is high impedance or infinity. So reflection at...

okay guys i have a small problem relating to network data transmission i have two cables cable 1 :- Bandwidth = B1 and SNR = S1 cable 2 :- Bandwidth = B2 and SNR = S2 Assume that B2 > B1 Cant i connect these two cables together and take advantage of lower SNR ratio requirements of...

This is from How Stuff Works: The power company essentially uses the Earth as one of the wires in the power system. The Earth is a pretty good conductor and it is huge, so it makes a good return path for electrons. "Ground" in the power distribution grid is literally "the ground" that's all...

I am at a loss on how to apply transmission line theory when a probe is connected to a high speed bus or for a matched RF line. For example, a signal going from a PCI clock to a bufffer which has a very short trace(so no termination is required). Now, if I connect a logic analyzer probe to this...

Am getting actually puzzled about some facts from telecommunication. When signal are transmitted from two mobile phones, the signal which is converted at the sending end from analogue by the speaker into digital on the mobile phone, does the transmitted signal actually wirelessly i mean is in...

I am currently building a solar panel. I have sheets of glass that I collected, some is saftey glass and some are tempered (probably the same). I have read that Low Iron Tempered glass has 91% light transmission. How do I test the glass that I have for its light transmission? Thanks

Homework Statement If I have a coaxial transmission line, with a resistor halfway through, and another resistor at the end, how do I calculate the reflection coefficient for the spot where the resistor is halfway? Here is a diagram of what I mean. Dashes and dots are are the lines, and }...