We’re rewarding the question askers & reputations are being recalculated! Read more.

# Questions tagged [resistance]

A measure of how much a conductor opposes current flowing through it. It can also refer to a part of a circuit, which has a non-negligible resistance value.

101 questions with no upvoted or accepted answers
Filter by
Sorted by
Tagged with
83 views

### Calculate sheet resistance in finite element method

I have a simulation with several polygonial mesh cells (Voronoi-mesh) and their centers of gravity $P_i$, each with its own electrical potential. Every cell has the same height $h$ all over. How ...
159 views

### How can I realize this nonlinear resistor?

I want to know if it's possible to realize a circuit described by the equation $$I = \sin(w V)$$ where $I$ is the current, $V$ the potential and $w$ a variable which characterizes the single ...
1k views

### Equivalent circuit to use when calculating the impedance of an electrical cable from its datasheet parameters

I'm trying to work out the impedance of a cable (specifically a single twisted pair of Lapp Kabel 0035836). The datasheet quotes the following information: ...
121 views

### Difference between using large vs small test resistance to check internal DMM/SCOPE resistance

For my intro lab to my Analog Electric Circuits class, one of the analysis questions is to calculate the internal resistances of the digital voltmeter and the oscilloscope, using the equation The ...
279 views

### Admittance calculation of a circuit

I am measuring the admittance of a circuit, by switching a load off and on at different loads. The admittance value I got from the measured voltage drop and current flowing through my circuit. The ...
966 views

### Power produced and internal resistance of solar cell vs distance from light source

Solar cell can be modeled (rudimentally) as a DC voltage generator $Vp$ with internal resistance $Rp$. Consider a solar cell at a distance $d$ from a (constant) light source. What kind of ...
748 views

### Why does a multimeter in resistance mode show initial continuity over a diode?

I originally phrased this question very differently; the original text is retained below in case background information is useful to clarify the context. When I using this digital multimeter to ...
169 views

### What's the equivalent resistance of this circuit?

I am a student in 10th grade and our teacher gave us this schematic to work with (Remade with circuit lab): simulate this circuit – Schematic created using CircuitLab He asked us to find the ...
28 views

I have one question with this topic: lm35 Temperature Readings are not right after sealing with Hot-melt adhesive (How mush has it Soldering max Temp toleration ?) it answered by this (Thanks from @...
58 views

### Problem calculating fuses

I am calculating a fuse and I'm having a bit of trouble. I have a 12v 2A power supply that I want to protect, so my first thought was to place a fast 250v 2.5A fuse in series so it should blow if a ...
53 views

### Effective resistance of a NMOS

How do we calculate effective resistance of a NMOS, operating in linear region across drain and source?
66 views

Admittance is the reciprocal of impedance. But: 1) Susceptance is the reciprocal of reactance, or the imaginary part of admittance ? 2) Conductance is the reciprocal of resistance, or the real part ...
51 views

### Calculating equivalent resistance using loop analysis with no applied voltage

I have a bridge circuit that I am supposed to find an equivalent resistance between points K and P for using loop analysis. I am aware that a delta Y transformation is the much more direct route, ...
70 views

### Finding equivalent capacitance and resistance from DC circuit with combinations of R and C

In order to get the simplest RC circuit and get equivalent circuit tau: How can be its transient studied if before t = 0 there only exists one resistive part of circuit? I's obvious that before t = ...
54 views

### How to find current through series of potentiometers, and if it is safe for potentiometers? (Arduino)

I have 9 potentiometer with the specs: 10k Ohms and 0.5W I'm using an Arduino Mega, and using it's 5V port output to power these potentiometers in series, and I saw online that the max current this ...
95 views

### Electric heating for glass melting furnace

Some furnaces use electricity for glass melting. Low voltage and high amperage power is passed through the molten glass through 2 molybednum electrodes dipped into the glass. The molten glass acts as ...
64 views

### How do I calculate total resistance?

As far as I understand, two resistors are connected in parallel if the node at both ends of both resistors are the same. And in series if only one node is the same. But what if between two resistors ...
50 views

### Measuring resistance of switched load

I am in the process of designing a custom vaporizer. So the main coil with a resistance ranging from 0.2 Ω to 2 Ω is switched using a MOSFET shown in the circuit diagram below. ...
35 views

### Evaluating the equivalent resistance

simulate this circuit – Schematic created using CircuitLab I want to evaluate the equivalent resistance. For that, I noticed R1, R2 and R3 are parallel connected resistors, which yields \...
101 views

### Y-Δ transform proof using superposition

In the Wikipedia page and in every book they prove the transformation by equaling the equivalent resistance between any pair of terminals while disconnecting the other node. https://en.wikipedia.org/...
129 views

### Eliminating the resistance variable in the total resistance/reactance equation of a series RLC circuit

Assuming that we have a simplified equation from a simple series RLC circuit where the total resistance/reactance in the series RLC circuit is equal to 100 times the resistance R: How do we modify ...
765 views

### How to make a open-circuit cable fault detector?

There are projects like this one over here: Underground Cable Fault Distance Finder, which checks if a given line is short-ciruited with any of the other lines. The location of the fault is also ...
149 views

I've found a something quite odd with measuring the resistance of a 36uH inductive load (see this earlier question). I can measure the resistance, which is quite low, but then disconnect the probe and ...
2k views

### Finding Values of Rd and Rs to satisfy the N-MOSFET design

I've been stuck on this design problem for a while and I am just filled with a lot of equations and unknowns and not getting anywhere with it. Here's a picture of the problem with the problem ...
76 views

### fuse metal alloy with high springiness?

Is there a fuse alloy that would have the same springiness as this except with a little wire that comes out and that plugs into something, so that it could be machined and pressed from one single ...
214 views

### High resistance (100Mohm) control using constant voltage or current source

I want to control resistance (100Mohm) programmatically. I found on this site that photoFET can solve this issue by sourcing constant current. From my understanding FET can give resistance control ...
116 views

### Analyse data discrepancies: Efficiency of wire vs current

Please help me explain why the efficiency of the wire does not follow a distinct path (ie R^2 value is low). Graph 1 Efficiency of wire vs current: http://postimg.org/image/p49bzm4ab/ Is is to do ...
82 views

### How do construct a electrical resistance tomography apparatus

Im interested in constructing an electrical resistive tomography setup to image underground structures. While I somewhat understand the principle, I have found limited information on design and ...
2k views

### resistance measurement problem with digital multimeter

I accidentally caused a short circuit with DMM common lead while measuring 220 AC voltage. then when I tried to measure resistance it gives me a reading of 3500 ohm while there is no resistor ...
266 views

### Do i need a resistor in this led circuit?

I have made a circuit with two (3v) LEDs in series. Connected to a 5v supply from an adapter with usb. (1.5Amp) I belive in series circuit each led gets around 2.5v which was enough to light them. ...
51 views

### How does an e-cigarette dry tank protection sensor work?

E-cigarettes work with a resistance coil which heats liquid into vapor. Some e-cigs have a dry-tank protection, which senses when the coil does not have any liquid to heat, to avoid it getting too hot....
34 views

### Finding Equivalent Resistance - does order matter?

Conceptual question: When you have a super complicated circuit, does it matter which node you start at when finding equivalent resistance? How about capacitance?
24 views

### Role of independent and dependent sources when calculating equivalent resistance

There are plenty of topics about this question, but I did not find a precise answer. Let's consider two points A and B of a generic circuit and suppose you want to find the equivalent resistance ...
43 views

### Reading of megohm during ground check

During the check of pins on connector with a multi-meter, one of the pins that goes through the relay to provide ground signal, I am getting 8MOhm (8 megohm). I should not be getting anything on that ...
23 views

### Thermal resistance of Thermal Interface Material

Can anyone please give information how to calculate the thermal resistance of SIL PAD "TSP A2000" from make Berguist. from The data sheet its specified thinness is 0.254mm, Thermal conductivity (W/m-...
103 views

### How a circuit get short

I am a high school student learning about the circuit, and how the current choose the path with low resistance, I have seen circuits and how one of the resistance among the other resistance get short....
52 views

### Find armature resistance on DC shunt generator

A DC self excited shunt generator has a field resistance of 160ohms generated emf is 420v and supplies a load of 55kw how would u go about calculating armature resistance when terminal voltage is 408v ...
38 views

### Thevenin Resistance in a op amp circuit

I created this circuit and I am struggling on trying to figure out the Thevenin resistance for this circuit.
82 views

### How can a light bulb run on different voltages (USA and EU)?

There is a concept in EE I don't understand. In Europe we have a 230 V supply voltage and in the USA e.g. 120 V. Now the thing I don't understand, how can I use my charger( or a light bulb) in ...
22 views

### To evaluate equivalent resistance of the circuit by star delta method

How do I evaluate this circuit via star delta method?
32 views

### ajustable resistance and MP2307

i try to make a current 4.2v with the switching regulation methode as you can see in the attached picture. The problem is that when i ajuste the voltage manualy from the ajustable resistance to 4.5v ...
36 views

### What is the Rseen from this node?

In the text book I am reading (CMOS Analog Circuit Design by Razavi) the author wrote that the Rseen from node N is (1/gm7), however when I derived it myself I found that the Rseen is ro4 // ro6 (...
63 views

### Calculating heat generated by resistance wire on 3 phase current

I am designing a heating element consisting of resistance wires coiled around a tube to heat water flowing in the tube. All three heating elements (loads) will have the same resistance and will be ...
59 views

### Best conductive ink mixture for potentiometers

Im 3d printing a model for a 2 axis potentiometer, and I need a carbon ink mixture that will hold up to the copper wiper, and produce around 10kOhm resistance in a line around 1mm*6mm. Searching ...
40 views

### AC resistance of LVAC transmission line

I'm currently working on a project to determine the transmission losses in an LVAC line, as part of an off-grid distributed generation system. The manufacturer of the cable has given me a DC ...
47 views

### What additional factors need to be considered when calculating voltage drop?

Considering the following formulas for voltage drop, what additional factors need to be included and how can resistance be derived to thoroughly calculate theoretical voltage drop for multiple ...
30 views

I have a pair of ATH-M50 headphones where the right side has stopped working. I took them apart and measured the resistance at the L/R terminals on each driver. The good one measures about 35 ohms ...
57 views

### Calculating source voltage in circuit

Given the circuit I have to find the source voltage S and unknown resistance R3. It is stated that the power dissipated in R6 = 3 ohm is 0.75W. How should I attempt to solve the source voltage where ...