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.
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Why do resistors have different tolerance bands if two or more are made similarly
Suppose I take a cylindrical graphite core and coat it with a thin metal film to try to make a resistor. Then I cut a helical groove into the film, add protective layers and leads, and complete the ...
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What material are the wires made from on axial-lead resistors? [duplicate]
The color of the wires is "silver" or grey. However, I don't know if it's aluminum or not.
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Current Mirror: Output resistance of stacked MOS used as current source
I am trying to calculate and simulate the output resistance of a stacked NMOS transistor used as current mirror load and I have a few questions about hand calculation and simulation setup.
The circuit ...
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Effective resistance of a finite grid of resistor
I have computed the equivalent resistance between two opposite vertices of a square grid of resistor using just the rule for series/parallel. I found many discussions on these, but cannot find a ...
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Why does resistance value in a MegOhmMeter dip when touching an unrelated conductor in a 8-conductor low-voltage HVAC CL2 cable?
Am using Klein tools ET600 to check if there is any hidden short to ground (like nail touching any conductor) in any of the 8-conductors in a 60 feet HVAC cable running from indoor air-handler to ...
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Is it common practice to add a capacitor to a voltage divider?
I came across a circuit module that uses a voltage divider to measure the value of a resistive sensor. However, unlike a simple divider made of two resistors, this one also includes a capacitor ...
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Nichrome wire foam cuber [closed]
Being at best handyman level, I need help on how to wire up a system of nichrome wire to recycle foam into cubes. My frame would be 24" x 24" with wire spaced 4" apart. I assume I ...
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Finding input resistance
I am trying to find the input resistance for the following circuit, but struggling to know where to even start:
From general method of connecting a known voltage source to find the input current does ...
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Strange or normal ohmeter measurements of IRF630 N-channel mosfets
10 new (bought on ebay) IRF630 N-channel mosfets. For all except for one of the 10 mosfets measured the following on an old multimeter on ohms x1k scale which I think uses 9 V battery.
Momentarily ...
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Can I divide potentiometer resistance in a way that is relatively linear? [closed]
I need to vary the resistance between two points in a circuit, so I bought a DS3502 digital potentiometer to use as a rheostat. The issue is that I made a rookie mistake, and thought that I could vary ...
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Why does my resistance in the LC tank circuit appear different?
I created a parallel LC tank circuit in LTspice. I want to use the input impedance of the node "A" in the diagram below. For this purpose, I drew the V(a)/I(R3) cross-section, and the ...
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When is it appropriate to use complex impedance vs. just magnitude in RLC/RC circuit analysis?
To put it briefly – how do you know when to use complex numbers in RLC circuit calculations, and when it's enough to just use the magnitude of the impedances?
Some context.
While trying to understand ...
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How to Use a BLDC Motor with VESC to Create Adjustable Resistance for a Stationary Bike?
I'm working on a project to convert a regular bicycle into a stationary exercise bike, and I'm exploring the possibility of using a BLDC motor controlled by a VESC to create resistance on the rear ...
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Optimization of liquid Electric Conductivity measurement
I want to design an EC measurement device that can measure the EC of a liquid from 0 uS/cm up to 20000 uS/cm. Right now, I'm using a voltage divider to measure the unknown R, with current flowing in ...
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Circuit with Resistance Inversely Proportional to Square of Input Voltage?
Is it possible to design a circuit that acts like a resistor, but whose resistance is inversely proportional to the square of the voltage supplied at the input?
This circuit would have one input and ...
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