Source Definition and 1000 Threads

Hello, I am experimenting with DC variable power supply and want to make sure I am using it correctly. My understanding is that it can output a variable DC voltage by turning the voltage know CW. The current-limit knob, as far as I know, is only there to set the maximum current that we would...

The WSJ and the NY Times, among other media sources, have their best sellers/new titles lists of published books. I seek the same but for STEM titles. (STEM is the acronym for Science, Technology, Engineering and Mathematics.) I can find such lists recommending history or biography or other...

Suppose I have a galvanic cell, where I've arbitrarily set the (-) anode to have a potential of zero volts and the (+) cathode to ##\epsilon## V. The electrodes are connected via the load, but also via the solutions and salt bridge in the centre. Edit: The two trailing wires are connected to a...

Hey, I want to try to estimate the Roentgens/sec from an X-Ray tube. Here are my calculations, which I talk through so that I am not just throwing equations at you. I would be grateful if someone could comment if they are about right. Stage 1: Estimation of emitted X-Ray strength Assumed: 1...

Most of the salt in seawater is sodium chloride. From my understanding, the primary source of sodium is the errosion of magmatic rocks, which contain lots of feldspars, the most abundant mineral in Earth crust. On the other hand, I don't know any abundant magmatic mineral which contains...

Summary:: I was trying to derive the equation for the output impedance of the ICIS circuit. Here's what I've tried so far. What I have derived does not agree with the one provided in my book. Since it is a current source the negative feedback must increase the output impedance. The one I...

Hi I need to create a electricity generator, I've got plenty of car alternators and car batteries, all are 12v. I know how connecting batteries in parallel / series, basically i could connect like 20 car batteries to have a 12v massive amperage power bank which would cause an issue with wire...

Tektites are small (up to a few centimetres), natural glass nodules, shaped as ovoids, spheres and dumbbells. They are found in about ten areas of the Earth's surface. In the 60s and 70s their origin was debated. Possibilities included volcanic ejecta from terrestrial or lunar volcanoes, or the...

In heat engine we define a heat source from where heat is transferred to the system, we say that heat source has a temperature ##T_h## , When we define a Carnot heat engine, the first process we have is an isothermal expansion and we say heat has to come in system through this process and here...

I need to create a powersupply that takes in a +5 and -5v and has an adjustable output that varies between -2 and +2 v using one potentiometer. I already came up with a design myself but it did not work. I need some help figuring this out. I think my idea for how to get specific positive or...

Hi, I was just wondering about the efficiency of a cycle that is not Carnot cycle. In that case one should use \eta = 1-\left|\frac{Q_{\rm out}}{Q_{\rm in}}\right|, where Q_{\rm in} and Q_{\rm out} are the amounts of heat absorbed and released during the cycle. For instance, I guess that in...

I'm having trouble understanding what it's asking me. "Calculate the angles at which the nodal lines in the pattern are located far from the sources." I assume they are very far away, making lines PnS1 and PnC parallel. Is the question asking me to calculate θ' in the example? "nodal lines"...

I am interested in knowing how to calculate the gravitational wave (GW) spectrum with inflation as a source, I have some background in inflation but I am not so familiar about calculating the GW spectrum. I am reading a paper (https://arxiv.org/abs/0804.3249) about it, however, a big part of it...

I need a citeable source that gives the formula for the Gaussian curvature at a single point of an intrinsically defined Riemannian or Semi-Riemannian manifold given the intrinsic metric tensor and/or Riemann tensor. I've got sources for this already, but I'm not "allowed" to use them for this...

Hi all, I was trying to solve this but I'm stuck as you can see in my notes below: Using simulator the I1=3.125 A | I2=-1,857 A | I3=4,375 A and Power of the dependent current source = -46.875 W Any idea, what could be wrong ?Thanks.

TL:DR; I've started an open source C# physics library: University Physics The Long Version So it turns out there's relatively little in the way of full physics libraries written in C# (the best I can find is bepuphysics which seems to be focused only on classical mechanics). With this...

Gravity batteries intrigue me. We are starting to develop them now. We currently are able to drop cement blocks and harness the energy that the kinetic energy releases. We are considering them as an alternative energy source to help the environment. Here’s a link for those unfamiliar with it...

Hi all ! I want a confirmation for this exercise please. The circuit: This is my try: https://www.docdroid.net/EFuTDMp/new-doc-2019-10-03-234340-1-converted.pdf -- Thanks

so when I did this problem I did nodal analysis to find the voltage across the 40k resistor, and found it to be 16V. From there I did two source transformations, combined the sources and did some equivalent resistance to get the answer as seen below: However this differed from the answer he...

I am so sorry if I am posting this in the wrong forum; it is just not a homework problem, and I can't find the right place - it's more of a study help question.

Hi all, I tried to solve this, but I can't find the R(equal). I use the following method. The circuit: For t<0 the switch is closed so the iL(0-)=4 A For t>0 it opens and the iL(∞)=0 A Now, I want to find the value τ=L/R(equal) Then I will use the: iL(t) = iL(∞) + ( iL(0-) - iL(∞) )* (...

In this paper, Cramer references a Sagnac source and mentions it has a half wave plate to vary the entangement vs. coherence by rotating the plate. Look just below figure 1: https://arxiv.org/pdf/1409.5098.pdf What is this setup? My guess is that the half wave plate is right before the...

Hi, Does the distance between the light source and the slits matter? Does the interference pattern change if you move the light source closer or further from the slits? I read from this link that the collimation of the light changes with distance and that affects the interference pattern...

Basically, I'm wondering how you can essentially determine the bearing of a signal source, if you know its signal strength. assuming you're in a vacuum, and you have a beacon transmitting a signal, and you know its signal strength. How could you find out the bearing (direction) it's at, if you...

One property of series resonance circuit is that at resonance, the voltage across circuit elements R,L and C may be larger than the source voltage. I can relate it to vector analogy where component vectors may have larger values than the resultant and the phenomenon is counter-intuitive. This...

It says that since there is homogeneity in the Universe's temperature, all these points must have come from one source (or a source close to each other?) at a certain time. Then it also calculates the number of these sources and it's ~105. But isn't that very dense mass right before the Big...

Interesting article ...NEW SOURCE OF SPACE RADIATION: Astronauts are surrounded by danger: hard vacuum, solar flares, cosmic rays. Researchers from UCLA have just added a new item to the list. Earth itself.“A natural particle accelerator only 40,000 miles above Earth’s surface is producing...

Suppose we have a light source emitting photons isotropically at a constant rate. Call the rest frame of the source S’ and call the photon-flux-density in this frame ##\sigma ‘##. (I’m treating it as a scalar instead of a vector because I’m assuming the light should travel radially in either...

Summary: FRB's source as Rail and/or Coil Guns (or mass drivers) Hello, I've been studying rail and coil guns recently, and certain applications of this technology can result in some pretty high speeds with a significant amount of mass. I've been wondering if these FRB's could be a result of...

We can solve for the maximum 5 lux illumination distance with the above equation. E = 10.76*(35,000/d^2) d = 275 feet (approximately). However, the 5 lux illumination distance is not 275 feet. The 35,000 cd value is not an axial intensity value. It is at a point that is slightly down and to...

Hi folks, I love doing integrals, and I think I'm going to start a competition at my school. The integrals in the standard calculus textbooks I have access to, Briggs, Stewart, etc., are pretty elementary. I am looking for some harder integrals. I have the books Irresistible Integrals and...

Got an electric water heater in my flat, one of those instant ones. It outputs a low flow but this is alright as you mix the hot water with cold water in the shower. Problem is, in the summer you need to mix in too much cold water in the shower and the heater shuts down, probably as it senses...

Thinking of 2019 and what kind of information we are being exposed of; What do you think is the most ultimate energy source that should be used from now on?

Hello, I was wondering whether blogs (especially corporate blogs) are good source for research. In some cases, such websites give me facts that hardly found elsewhere. However, when used as research source, corporate blogs can present problems: there is no way to know the credibility and...

If you place a zinc / copper battery it will create an electric field pointing from the copper to the zinc and my question is this what makes this electric field , the zinc pushes electrons in the circuit and never "stays" negatively charged for an electric field to be created same for the...

So I understand that when an electric field is produced in a conductor of length L, the net electric field in the conductor will be 0 because the rearrangement of electrons in the conductor results in the production of its own electric field which cancels out the one produced initially...

Hello everyone! does anybody know How can I calculate a distributed radiant flux of an IR source in a space? Is there any software or something?

I have found plenty of information about the radio source Hercules A. Its large radio jets are 1.5 million light years long from end to end, the supermassive black hole that produces Hercules A is 3 to 4 billion solar masses, and the black hole exists in the center of galaxy 3C 348. However, I...

Summary: Kindly explain the source code in R which meant for calculating stationary distribution of a transition matrix. I am trying to understand the following source code meant for finding stationary distribution of a matrix: ### Stationary distribution of discrete-time Markov chain ###...

#================================================================== # Build the transition matrix for random walk on n-cycle #------------------------------------------------------------------ n <- 25 # we are creating (nXn) transition matrix r1 <- c(0, 1/2, rep(0,n-3), 1/2) # create same...

Hello everyone In my study, I inject a different amount of fluid in each experiment, such as 1 ml, 2 ml..., and test the change in the general dielectric properties of the solution. Now that I have done much (over 100) measurements for each injection in a specific volume, one can see that for...

hi, all great brains, I have a question about BVP, which confused me a while, maybe someone can help to clarify it. For a point source with Dirichlet boundary in a 2D domain, the response at any coordinate except the source point is dependent on the surface of the source, for example, heat...

hi every body i use MCNPX with a Z600 with 20Go of ram and 16 core to calculate the dep energy arrownd a source of cobalt with the tally F6, but when i put NPS=3E+9 an erreur apears that '' all entries must be integers''. i want help because NPS=2E+9 dosn't give a satisfaying results?

My attempt: At node 1 > 4 = 6 + I1 Node 2 > I1 + I2 = I 2 Node 3 > 6 = I 3 + I 4 I1 = (V1 - 4)/21 In node 1, Using the equation for I1, V1 = -38V. I2 = (V1 - 4 - 1)/2 So, I2 = -21.5APower supplied by the 1V battery is P=VI P=-21.5 x 1 P=-21.5W I am not sure of my method, I just started...

I am having a discussion with a friend who advocates "ozone therapy": re-injection of your blood after being enriched with ozone, done by a doctor. Since I am very skeptical of this fad (all I can see is that ozone destroys double bonds in carbon chains, which does not seem like a good thing--...

Let's say we have a wire and a circuit is closed the magnetic field start to spread with speed of light c. Then we would have a place " out of range " at which the magnetic field doesn't exist.What is the equation that connects magnetic force with distance with its prorogation of speed of light...

Hi all, I am hoping someone could clear up a concept that doesn't make sense to me. I am thinking in terms of a blackbody diagram, which is "Intensity" on the y-axis and wavelength on the x axis. I understand that when you heat something to a higher temperature, the curves shift to shorter...

I would upload it soon

I need to calculate irradiance in a system shown on the image. There is an infrared LED on the left and a diffuser in front of it. I need to calculate irradiance at a certain distance after the diffuser. I think I first have to calculate irradiance at the diffuser. Then multiply it by the...

I am attempting to build a sodium iodide detector on MCNP. I am using a disc source and I have been trying to define it in terms of a cell that I placed underneath the detector. When I run it, I get 0's for my counts. This indicates to me that my source isn't hitting my detector. I keep...