Source Definition and 1000 Threads

Just to clarify the title... Basically for the below circuit we are required to find Vth, Rth and Vo. However, the method of solving this problem is a little strange to me, because as you can see, the source has a phase angle of 30 degrees. The solution to this problem basically says (to find...

Hi Just finished the chapter on the Multiverse in David Deutsche's excellent book The Beginning of Infinity. His explanation of how discrete values change from the multiverse perspective is brilliant. In it he explains that there is no such thing as a 'quantum jump' and that what 'changes'...

I've been going through some materials, and I was reading about electric circuits. From what I read I figured that the electric current is dictated by the current source, and it's preserved(in the respectable branches) by the emf. Is that right? Or my feeling that I'm way off is true :)

Hi. I was wondering if someone can provide me with some advice on the proper way for measuring the optical power of a pulsed laser system? My optional methods are: - Photodiode detector: measuring average power - Oscilliscope with optic-electric converter...

Dear All, I am working on digital image processing. I want to do texture analysis. I need computer vision source code. I could not find the source code. If you have these source code please share me.

Firstly i need to heat a wire to around 20 degrees or over using a low power battery which could last up to 24hours. what kind of wire is easiest to heat up? would AA battery's work? what would be a long lasting battery source? can it be done? please help me! thanks

I understand that I should be able to see the source for formulas/equations/math symbols people put in their posts, by right-clicking a symbol or equation. I seem to recall that I could do this but I am unable to do it now in Firefox (Ubuntu Linux Lucid). Is there something I need to install...

\text{In}[1]:=\text{Solve}\left[\partial _{\theta } \text{Sin}[\theta ]==0,\theta \right] \text{Out}[1]:=\left\{\left\{\theta \to -\frac{\pi }{2}\right\},\left\{\theta \to \frac{\pi }{2}\right\}\right\} Is there a Mathematica source code command that can read a specific numerical value from...

I have been working with a large number of triodes amplifiers in parallel pulesed by a large thyratron tube. Earlier, many of the triodes decided to arc and melt. The amplifier was huge and I need to replace it. I need a design for a microwave source that is small and more powerful (megawatts)...

why can't we harness the energy in lightning? it seems to be an unending supply of electricity.

Knowing that light goes on in infinity. Would it theoretically be possible to trap light between two mirrors? And have an infinite source of light which would require no energy once it has been trapped.

Consider the email message source below, and answer the questions that follow. Return-path: <xxxx@xxxx.xxx> Received: from cs.smith.edu (scinix.smith.edu [131.229.72.8]) by gwsmtp1.smith.edu with ESMTP; Fri, 29 Apr 2011 10:17:33 -0400 Received: by cs.smith.edu (Postfix) id D8D19EEC01...

Can sound from any source create thrust?? hi there, since I'm new to this forum, i don't know whether this the place to put up a question like this...! if I'm wrong my sincere apologies let me head to the topic now... i wanted to whether the sound waves created form any source can...

If a "line" source of visible light is not really a line but has a width of 1mm, how far must it be from a double slit which it illuminates in order for the two slits to be reasonably coherent? Assume the slit separation is .5mm. I approached this problem the same as finding the distance...

This question has been driving me crazy because i am unsure when i am able to apply voltage division to portions of a circuit i try to analyze. I know the potiential difference across a voltage source always needs to be equal to the value of the voltage source but, if the branch coming out of...

Hey guys I'm just wondering if I'm on the right track for the problem. I have started analysing the circuit, but I'm really unsure of my method of analysis. Did I use the formulas correctly? :confused: The circuit switches from position "a" to position "b" at t=0 and I'm trying to fined...

hi :smile: I'm having some trouble figuring out the Thevenin equivalent for this circuit. As you can see, there are two dependent sources (current dependent current source & voltage dependent voltage source) and no independent source. I have started trying to analyse the circuit by...

Homework Statement A practical current source has a current of 22 A. Loading the source with 50 \Omega results in terminal voltage of 390.3 V. Obtain the source constants, I and R.Homework Equations V=I\times RThe Attempt at a Solution In my clumsy picture below, shouldn't I_{load} be replaced...

Greetings, I have a problem that's been bugging me for a few days now. I've asked electrical engineers, students and graduates, and I can't seem to find a clear-cut answer to these questions. THE SCENARIO One piece of copper wire has one end connceted to a terminal from a multimeter...

In Bird, Stewart, Lightfoot "Transport Phenomena", they post the following equation for heat conduction with a nuclear heat source: Sn=Sn0 [1+b(r/R)^2] where Sn is volumetric thermal energy, r is radius and R is radius of the fuel pellet. The text state that b is a dimensionless...

If a circuit schematic contains a current source, is it safe to assume I(total) is that value?

Homework Statement a 500 ohm resister is fed by 120 Volt P-Peak ac source;How much heat does the resister dissipate if the signal is a sine wave or a square wave? Homework Equations The Attempt at a Solution

Hello everyone,:wink: I am having difficulty understand the concept of current source and what it really is. I have written down below what I think of current source. Some things I said will be wrong and there could be possibility that some are not wrong!:-p Now you help me out please. Much...

Hi, this year I am applying for university, undergraduate course. I'm interested in physics and looking for course connected with alternative source of energy, like from new type of batteries to solar energy to nanoenergy. What type of faculty should I attend? I'm not fond of studying...

What I mean by the title is, why isn't it more popular? (I know there DO exist some hydrogen powered cars.) To me it just makes sense to use hydrogen. It is very explosive and it's byproduct is water! The only draw back I can see is storing the gas in the vehicle to be used. Can anyone...

Hello i need a 9VAC 1.3A source but it's hard to come by... is there a way i can use a similar source? i don't know too much about this sort of thing but from what i understand the power output is more important than the individual current or voltage out... is that right? for example, my...

Greetings, I am rather clueless about this stuff so I'll leave it to you guys to come up with any bright ideas for this. I'm building an array of LED's for my high school that flash to music. I'm using a TIP31C transistor to get this effect. My problem is they're wanting a 1 foot by 1 foot...

May anyone please help with the method of getting Thevenin Equivalent resistance (RTH) for the attached circuit. I have already found VTH to be 8V. Sim

Homework Statement Determining the resolution for a new PIPS (Passivated Implanted Planar Silicon) detector. I've done this earlier for a Ge detector, but that was easy because the two peaks of the Co-60 are far apart. For this measurement we use the normal Am-241 source which has two...

Hi everybody. Apologies for asking what may be a very simple question, but in every textbook I've read, they say that the net flux through an area dA from an isotropic emitter is zero. But it also says that the sun is an isotropic emitter. Now hold on, the net flux from the sun is clearly...

Homework Statement My books states, considering a stationary source emitting waves at frequency f, such waves having velocity v, and an observer approaching the source along a linear path at velocity vO we have that: The observer registers the velocity of the waves at v+v0. Up until now all...

this question is part of my electronics CW, I've done it before, but briefly. and looking back at all my old notes I've realized that every single one I've done before has 2 sources and only 2 loops, whereas you can see from the image below that this has 3 and its getting me in quite a...

Homework Statement Find Rthev as seen by terminal (a,b) http://cid-3c099006138591f8.office.live.com/self.aspx/Pictures/IMG^_0337.JPG Homework Equations Can somebody point me to the right method to solve this problem. I know how to solve when there is a dependent source, but the dependent...

hi, i got a question about mna. i know how to write matrixes with(out) voltage source but i don't know what i should do when my instructor askes me placing vcvs or vccs instead of any resistor. i have lecture notes for vcvs ust like; Vpq=u(mu)*Vkl i should add extra rows and cols. to matrix of...

why the internal resistance of energy source or cell is shown in series for voltage source and in parallel for current source? thanks.

Consider the following circuit. Using superposition determine a) the magnitude and b) the direction of the current going through R_1 (is it away from node a?). Dtermine the c) magnitude and d) direction of the current through R_2 (is it away from node b?). e) Find V_{ab}. a) First, I will...

All electron flow nuances aside, let's look at simple circuit analysis. Hopefully you guys can clarify something for me. Say we have to drive an LED. We have a +5V source, a 3.4V forward voltage, and a 150 Ohm current limiting resistor: +5V --> Resistor --> LED --> GND Okay, so let's...

Had a quantum assignment recently and one of the problems was: What is the photon flux (photon cm^-2 s^-1) at a wavelength of 600nm at a distance of 1km from a blackbody soiurce at 2000k emitting 50W of radiation between 400nm-700nm. My thinking was: This involves Planck's radiation...

I know that nuclear fusion is the source of energy for our sun and most of the other stars. Neutron stars and white dwarfs have very high surface temperatures. What is the source of their energy?

Ive heard it said that electricity and megnetism are brought about by electromagnetic waves, but arent electric forces the cause of the other 2?

Homework Statement Suppose we have a circuit with the inductor, uncharged capacitor, ideal battery with emf E all in series. At t=0, the circuit is switched on. The following takes place sequentially: 1. Current at t=0 is max. Battery charges capacitor, current decreases. 2. inductor...

Homework Statement An emergency supply consists of a small diesel engine driving an alternator. The output of the alternator is rectified and smoothed to produce DC. This has has to supply 10 amps of 110V emergency lighting and charge a 110V battery of internal resistance 2 ohms, If the...

i understand that there are times when one should (on paper) pump a network of resistors, capacitors, and inductors with a 1 amp ac current source or a 1 volt ac voltage source in order to determine certain values within the system however, i am having trouble determining when i need to use...

Trying this again from a different angle... Let's say we have a 120 Volt AC source. We'll call it a generator. This generator is not touching the earth. Let's just pretend that it's suspended in mid air with nothing at all connecting it to the ground (the earth). On this generator, there...

Homework Statement Imagine that the source is to the right of the listener, so that the positive reference direction (from the listener to the source) is in the +\hat{x} direction. If the listener is stationary, what value does f_L approach as the source's speed approaches the speed of sound...

Suppose a capacitor is initially charged up to 2V, and then a 1V DC voltage source is used to discharge the capacitor to 1V, what is the energy consumption from the voltage source and what is the total energy loss? Assume the capacitor is connected to the voltage source using a resistor and...

Aim: To measure the acceleration due to gravity using a simple pendulum. source of error 1. The length of thread between the bob and the coins is not measured by very accurate instruments. Since meter ruler has a large percentage error, as a result, it should be replaced by a vernier caliper...

Homework Statement A point source power outputs a power of 100 W. If a decibel reading of 118 dB is heard, what is the distance to the observer. Homework Equations I = P/(4*pi*r^2) The Attempt at a Solution This should be simple, but for some reason my numbers aren't matching up...

I hooked up four capacitors in parallel to a solar charger and found that they all acquired the same voltage. Why is this? I thought that capacitors took energy from the source, which would imply that the second, third, and fourth capacitor had less voltage than the previous one.

Homework Statement A two-point source interference pattern is generated by sources operating in phase at 1.0 Hz. The sources are 2.0 m apart and the wavelength of the waves is 0.60 m. At what angles, measured from the centre line of the pattern, are the nodal lines produced located...