Loop Definition and 1000 Threads

Homework Statement FIGURE 3 shows the block biagram of the control of an electric heating system. The heater is driven from a voltage-controlled power supple, the voltage V1 being derived from a potentiometer. The output temperature, θo is subject to distrubances, θd, because of changes in...

I once drove my RC car in a vertical loop in a concrete drain pipe. If you know the diameter of the pipe, and the weight of the vehicle, what is the formula used to determine the minimum speed required for it to complete the loop?

Homework Statement In the figures below, a copper wire of circular cross section, A, has been bent into a square loop of side length, c, and arc welded at the seam for electrical continuity. Assume that the resulting square loop has a resistance, R, and a mass, M. The loop is originally held...

Homework Statement We have a circular loop of wire, with AB is another wire which is also the diameter of the circular loop. The direction of magnetic field is perpendicular to the loop, into the plane of paper. The magnetic field strength is decreased at a constant rate, without changing the...

Homework Statement An ideal, infinitely long straight wire carries a current I1 and is partially surrounded by a loop of current as shown below (image attached). The loop has length L, parallel to the infinitely long wire. The loop carries current I2. A) Calculate the magnitude and direction of...

Hi forums, Following is the hysteresis loop of a standard memristor: Please note that, the red one is for lowest frequency and black for highest frequency. From the graph, one can take the following observations: 1> As frequency increases, area of graph decreases 2> With increase in frequency...

I am trying to compute the cross-section for the diagram below with a divergent triangle loop: where ##X^0## and ##X^-## are some fermions with zero and negative charge respectively. I am interested in low energy limits, so you can consider W-propagator as ##\frac {i\eta_{\mu\nu}} {M_w^2}##...

I am iterating over 2 variables below and after the calculation are done, i'd like to append the dataframe to add the rows after each iteration, but what is happening now is that the row is getting replaced instead of getting added. pre = [10, 9, 8, 7, 6, 5, 4, 3, 2, 1] post = [0, 1, 2, 3, 4...

Homework Statement I posted this in the advanced section, but glancing over the problems there I realized this probably belongs here.[/B] Hello everyone. I hope this is the right category. I am in desperate need of help. I have no High School Education. But a few weeks ago I participated in an...

Homework Statement A 180lb pilot flies a verticle loop with radius 2000 ft at 350 mi/h. With what force does the seat fress upward against him at the bottom of the loop? Problem 6.21 Homework Equations ##F=ma## ##F_c=\frac {mv^2} {r} ## The Attempt at a Solution There seems to be a...

Homework Statement Discussions of the possibility of a tangential E-field external to a current-carrying conductor must include a voltage source and a return path. Here the problem is reduced to (we believe) the simplest possible geometry. Assume that a circular conducting loop has constant...

i have keithley currnet source that i control with matlab, inside a loop, if i force stop the loop the device continue to output the last current. my question is can i add if condition that turn of the current source? for example if force stop fprintf(device, ':OUTP OFF') end

Homework Statement [/B] ∇ * B = 0 and ∇ X B = Mu * J. This is proved to hold not only for infinite wires but for magnetostatics in general. Magnetostatics = steady current Closed wire loop with constant current is certainly a magnetostatics example. Magnetic field on z axis above loop around...

when a square loop is stretched to make a rectangular or circular loop(wire length remain same) in uniform magnetic field into the plane of paper what could be the direction of induced current. please share explanation as well

Hi, I know that Python supports parallel programming. I think it can be used in my case but not sure how. Basically I have this for loop out = [] for value in vec: out.append(func(value)) where func is some function that takes value as an argument. The different values in vec are...

hello i have a few questions regarding hysteresis loop in ferromagnets as showen here . i had an experiment in which i took a piece of gadolinium and cooled it down using liquid nitrogen , than i put it in an apparatus as showen here , so i induct an oscillating magnetic field on it , forcing...

Homework Statement A square circuit of resistance R=20Ω and side ℓ = 0,2 m spins 100 times per second around an horizontal axis that splits it in two. There is an uniform magnetic field B=1T perpendicular to the position ocupied by the circuit at t=0s. Calculate (1) the magnetic flux, (2) the...

Let's say you have an open loop (like a section of a circle) in a changing magnetic field. I think there would be an induced EMF, but no current. What I can't figure out, though, is how to calculate the induced EMF. Using Faraday's law doesn't seem to help, as there's no enclosed area.

Homework Statement Homework EquationsThe Attempt at a Solution I am having a little doubt as to how to think of the moving electron as a current . I am considering the moving electron as a very tiny (infinitesimal ) current element . It is as if when the electron is at A , there is a very...

I have an ASUS X540S (a cheap $199 priced) laptop and it asked me to do an update a few days ago. I agreed and left it running to go to dinner. When I came back, it was in some weird screen asking me to select a language. I chose English and the next thing I know it was in some sort of loop...

Homework Statement Homework Equations T = IAB sin θ ; θ is the angle between B and I. T = μ × B The Attempt at a Solution A) T = IAB sin θ T = √2 a b I B (θ = 45°) B) T = 0 , because θ = 0 C) T = 0 , because θ =180° D) T = μ × B The direction of μ = -k , because the fingers points to the...

Hello Everyone. I Was Wondering how excatly the Gauge invariance of the trace of the Energy-momentum tensor in Yang-Mills theory connects with the trace of an Holonomy. To be precise in what I'm asking: The Yang-Mills Tensor is defined as: $$F_{\mu \nu} (x) = \partial_{\mu} B_{\nu}(x)-...

I already did a similar question here but got very little response so I will try to reformulate my question into a better one.So, the basic idea of the original question was whether a Faraday disc aka homopolar generator be made such as to have no sliding contacts and the load being attached to...

Homework Statement [/B] I need to calculate de radiation field produced by a charge moving in a circular loop of radius a, considering the motion is not relativistic and zone of radiation (far field) .Homework Equations The scalar potential is: $$ V=\int \dfrac{\rho(x')}{|x-x'|}d^3x'$$ The...

Homework Statement Homework Equations Kirchoff's Rule The sum of all V = 0 The Attempt at a Solution [/B] I think I'm having a problem determining the current at r_2 and R_3. I had originally thought the currents at both resistors would be I_3, writing E_2 — r_2 I_3 — R_3 I_3 — I_1 R_1 = 0...

Homework Statement Homework Equations Faraday's Law, Ohm's Law, definition of current[/B]The Attempt at a Solution We were given this solution:[/B] The above solution is leaving out a lot of intermediary steps. I don't agree that "the axis of the coil is at 20°, not 70°, from the...

Homework Statement This question is referring to the classic ball in a loop question where it is dropped from a height and slides into a loop de loop. Derive an expression in terms of theta the velocity of the ball at the time it loses contact with the track. Theta is measured from the...

Homework Statement Determine the B-field inside the middle of a circular loop of current. Homework Equations Attempt at using Ampere's law: ##\oint \vec{B} \cdot d \vec{l} = \mu_0 i## The Attempt at a Solution ##\oint B \cdot R d \theta = \mu_0 i \Rightarrow BR(2 \pi) = \mu_0 i \Rightarrow B...

Homework Statement Figure 6.47 shows a horizontal infinite straight wire with current I1 pointing into the page, passing a height z above a square horizontal loop with side length l and current I2. Two of the sides of the square are parallel to the wire. As with a circular ring, this square...

Homework Statement Homework EquationsThe Attempt at a Solution If we consider the bigger semicircular arc BD alone then potential difference between B and D will be 4BvR . If we consider smaller semicircular arc AC alone then potential difference between A and C will be 2BvR . If we...

Homework Statement [/B] A radio transmitter radiates isotropically at the frequency of 90.8 MHz. The peak magnetic field at a receiver, 9km from the transmitter, is ##9x10^{-10}T##. Calculate the maximum amplitude of the induced emf in a 12 turn coil with area A = ##90cm^{2}## at the receiver...

Pipe loops are used to accommodate thermal expansion. I have seen many types and lengths but here is one example: https://www.engineeringtoolbox.com/steel-pipe-expansion-loop-d_1069.html I am a little unclear on why they can work. With any thermal expansion the stresses on the elbow joints...

Homework Statement Hi, Here is what I know about the Ideal Op-Amp. - The open loop voltage gain is infinite - The output voltage is given by the following $$v_o = A(v_+ - v_-)$$ - Only with a negative feedback loop is $$ v_+ = v_-$$ My query is with regards to the negative feedback loop...

Dears Kindly, I want to hear from you regarding this topic. The system is closed cooling system. I believe it is difficult to attribute the sound you hear from centrifugal pump to be a cavitation especially if the discharge pressure is normal. The last time we had a problem with this system...

Homework Statement Homework EquationsThe Attempt at a Solution The area of the loop is π(b2 - a2) Emf induced E = Rate of change of flux = πk(b2 - a2) Resistance of the wire R = 2πλ(a+b) Current in the loop = E/R = [k(b2 - a2)]/[2λ(a+b)] . This doesn't matches with the given answer .

Homework Statement A straight copper wire that carries a sinusoidal current with an alternating frequency of 50 Hz and a maximum amplitude of 0.5 A passes through the centre of a circular ring of a second copper wire, with the two wires orientated perpendicularly to each other. The radius of...

Homework Statement Two beads with masses of M and m are threaded on a vertical loop with radius of R. M is released without velocity from a height of 1.5R from the bottom of the loop. The collision between the beads is completely elastic. What is the smallest mass M that will make the second...

Hi PF! I'm trying to compute $$\phi_n(x)=\pi x^2+\int_0^{\pi} 3(0.5 \sin (3x)-tx^2)\phi_{n-1}(t)\,dt$$ given ##\phi_0 = 0##. I'd like to iterate this computation until ##\sqrt{\int(\phi_{n+1}-\phi_n)^2}< 0.1##. I've never used the while loop in Mathematica, tried reading the documentation but...

Homework Statement Homework EquationsThe Attempt at a Solution When the circuit moves creates magnetic force that moves the some charges in the wire and that is a current. That is what i thought. F = Q.v B sin theta B = ( permeability Of vacuum* I)/(2pi.r) But how to find the I? Thank you...

I am taking an experimental course which requires us to conduct experiments by ourselves. One of the tasks is to demonstrate the flux pinning effect of a type II superconductor YBCO by magnetic levitation. The professor asked me to discuss the effect by using the hysteresis loop (magnetization...

Hi suppose you have a conducting liquid in a strong magnetic field, and this is pumped in a continuous loop through two electrodes, why does this produce a D.C current? My thinking is a simple answer, and that is that the D.C current is produce because the fluid is moving in one direction...

Hi all, I think this issue periodically resurfaces in PF. I have found a similar discussion in this closed post and possibly others. I'm posting this because I'd like to check my understanding, if anyone is available to provide some furtherinsight. So I'm trying to gather a "overall"...

Good , i want to derive the formula for field of a circular loop around its axis but i was stucked with the following point: they consider dl perpendicular to r ! why is that?? many thanks in advance!

I am relatively new to programming and C++ and for the life of me I can't figure out why entering a '0' as input in the do-while loop here terminates the loop. // vector::push_back #include <iostream> #include <vector> int main () { std::vector<int> myvector; int myint; std::cout <<...

Hello Everyone, I've been tasked with verifying the pump external static pressure for an infrastructure water supply network. The network is a series of loops as shown in the image attached . According to the calculation notes done by the designer, the design of the network was done in watercad...

Hi, I'm trying to calculate an integral which looks unfortunately divergent. The structure is similar to a loop integral but the appendix in the Peskin textbook didn't have a useable form. The integral form is (I did a u substitution to make it easier to look at) \int_x^{\infty}du...

Homework Statement The question is Derive an expression for the closed loop gain of the differential amplifier. I have solutions for these questions but the solution for this question is quite vague. Here is the solution: I understand part 1 and part 3, but part 2 I don't. So looking at...

Homework Statement The circuit shown is in a uniform magnetic field that is into the page. The total current in the circuit is 0.20 A, flowing counterclockwise. At what rate is the magnitude of the magnetic field changing? Is it increasing or decreasing? Square wire loop with base and height...

Homework Statement If the car is going 30 m/s half way up the loop and loses energy due to friction at a rate of 2.0J per meter of track, how fast will it be going at the top? (this is question related to the loop of roller coaster track, with radius 20m.) Homework Equations 1. Ki + Ui = Kf +...

Homework Statement Here is a link to the problem: https://imgur.com/a/0T9sF I am having trouble finding the time it takes the loop to leave the field in part a. Homework Equations ## emf=-\frac{d \Phi}{dt} ## ## \Sigma F=ma=mg-BIl ## ## \frac{dv}{dt}-\gamma v=g ## where ##...