Questions tagged [conductivity]
Electrical conductivity or specific conductance is the reciprocal of electrical resistivity
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Moving electrons on the surface of a thin metal sheet with high current
I don't know if this is the right place to ask this because my question is a mix of physics and electronics. I'm in 12 grade, conducting a simple physics experiment.
In the experiment, I have a very ...
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Freely rotating part that conducts electricity to fixed part - does this exist?
Planning a design that has a 12V voltage source connected to a physical part that rotates.
I need to conduct electricity from the rotating part to a fixed part which is connected (electrically ...
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Attaching terminal lugs to conductive case
I am wondering if there is a standard way to attach terminal lugs to a case that is conductive. I want to create an electrical connection that is mechanically connected with a screw. The issues with ...
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Low electrical resistance, high thermal resistance conductors
I was thinking about diamonds, and how they're excellent thermal conductors and yet at the same time very good electrical insulators.
Does the opposite of diamond exist, i.e. are there commonly ...
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If there are two electrical conductors in a circuit with differing electrical conductivities will electricity choose the most conductive conductor?
Say you had two parallel wires, one copper and one steel, copper having a much higher conductivity than the steel, will electricity choose to flow through the copper wire, ignoring the steel wire?
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How good of a conductor is laser-induced graphene from Kapton tape (polyimide)?
I had intentions of making a DC electromagnet using laser-induced graphene (LIG), where the graphene will be used as a flexible electromagnetic coil. Something like those 24V electromagnets you can ...
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What are the practical differences between solder balls and spherical tin powder?
Solder balls are made of tin, with small amounts of silver and copper. The minimum size of solder balls is limited. Nano spherical tin powder is available in smaller particle sizes. If such a tin ...
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Best grade of graphite powder for a conductive paste
I want to make a conductive paste using graphite powder mixed with a liquid binder.
The idea is to create heat through Joule heating when the (alternating) current is passed through the graphite, so I ...
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Why aren't stranded wires used more widely if conductivity is improved and price is reduced?
Why aren't stranded copper coated aluminum cables (CCA) widely used outside a small niche of speaker wires or 12 VDC applications?
According to this post the issue is with the insulation jacket which ...
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Highly thermo-conductive epoxies for potting
Some advertise as much as 2 W/mK of thermal conductivity. Free air is no more than 0.03 W/mK at usual temperatures. Air convection I think will be the same in both the potted and unpotted cases. Does ...
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How to coat a thin electrical wire with carbon?
I am looking for glue that can be used under a bio-solution. The solution is a bacteria culture solution (LB, SB). I have a chamber filled with culture solution and I would like to extend an ...
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How to correct PWM signal
I am trying to design something to test the electrical conductivity (EC) of water. Knowing that conductivity is the inverse of resistivity, my plan was to measure the resistance of the water via a ...
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Saltwater Measurement via Arduino
This is a strange question, but I'm trying to learn specific uses for all of the Arduino functionalities. If I were to program the Arduino to spit back the result of analog input into serial as seen ...
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Is there any difference between electricity flowing in earth vs. flowing in wires?
I wonder how the earth (real earth, not earth wire) works as a conductor in Single Wire Earth Return system, or in case of a fault in regular grounded systems.
How far can electricity flow in earth, ...
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Do antennas still radiate in a conductive medium?
Since normal antennas are placed in air or a vacuum, I was wondering what it would take to get an antenna to work underwater, especially in something conductive like seawater.
What would be the ...
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Minimum resistance of copper regardless of thickness
In a system where you have an unlimited amount of copper, is there a minimum or floor to the resistance?
Scenario would be a wire 24000 miles long, attempting to keep the overall resistance below 1 ...
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Current draw of an Arc Lighter
I have an arc lighter, similar to that which you can see here:
My question is this. I understand that you need a very high voltage, created by a transformer within the device, to create sufficient ...
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Why my wooden table and mouse pad on it measures 12 volt?
I have a non-contact type AC/DC tester which can test 12V - 250V AC and DC. When I put that on my computer table, it shows a 12V reading:
The tester that I have has no battery inside. So there must ...
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Why can't conductors be used in making ICs (integrated circuits) instead of semiconductors? [closed]
I really wanted to ask why we can not control flow of electrons in conductors.
Can I not say if a current is flowing in a conductor it is 1 and when I disconnect the supply it is 0.
Can you elaborate ...
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Fourier transform of the electrical conductivity function
In this pdf https://studylib.net/doc/18704299/chapter-1 the author writes that the Fourier transform of the current density is:
$$
\Delta j_{i}(\mathbf{k}, \omega) \equiv \frac{1}{(2 \pi)^{2}} \iiiint ...
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MOSFET current at very low temperature (4K)
I am trying to model the current at low T. To do so I need to compute the integral between the fermid diract statistic and the conductivity, with respect to energy. My problem is that I cannot ...
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Electrical conductivity circuit help, with two solenoids
I have a project im working on but cant seem to figure out the basic of the circuit.
The principal of the circuit is two solenoids wrapped around a chemistry glass making a magnetic field. The purpose ...
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Can someone explain this grounding phenomenon?
I went into a conversation with an electrical engineer. Here is what was on the table:
Me: How do you connect a two-phase load to a three-phase delta load? If the loads were Y-connected, then you ...
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Is there a name for this type of connection? [closed]
I can't think of a time when I've encountered this, but I think that this is a thing: you have two conductive paths that, when connected, become one path. How they become connected is through tension/...
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Thermal pads, their thickness and conductivity
I would like fo know how do thermal pads work, more specifically why does their thickness matter so much even more so than their actual conductivity numbers sometimes and how do I choose the proper ...
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Conductivity vs Attenuation
Attenuation of em waves, when they travel over a surface, happens because the em waves induce a current in the surface and loose energy. EM waves travel farther over sea/ocean. Conductivity of sea/...
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Need of semiconductor instead of conductors for changing conductivity
Is changing conductivity is one of the reason to use semiconductors?
When we can change conductivity of metals(by some means) then why do we need semiconductors instead in most of the electronic ...
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Low Power Toroidal Conductivity Sensor Inconsistent Values
I have been trying to build a low power toroidal liquid conductivity sensor using the principle given in this image.
This link has more information about the principle behind the sensor.
What I have ...
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Material selection of heating element
I am interested in heating coils which are heated using Ohmic/Joule/resistive heating - specifically, how the material for the heating coil is selected.
When I read about heating coil materials - ...
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Nichrome powder acting as a resistor
I’ve been doing some experiments recently with metal powders and I’m wondering if someone can help me interpret the results and give me some advice.
I wanted to test how the metal powder would work in ...
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Would you approve this soldering job? [closed]
I am new to soldering, and I am not sure if I did a good job while trying to solder some pins into a HX711. My concern is that the solder in SCK and VCC are touching (also E+ and E-), so I thought ...
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What is the TDS and Conductivity of Ice from freezer, when, it has turned liquid?
Condensation of water vapors makes it distilled. I was wondering if the Ice formed inside the freezer top chamber can be used as distilled water. I tried checking the resistance with multi-meter, ...
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Why no conductivity with this wire?
These are two ends of the same cable:
The cable comes from an old headphone set and I want to re-purpose it.
What are those copper looking wire strands? I could not get connectivity between them and ...
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Measuring conductance of the material used in fabricating Antenna
I have a composite polymer material with injected conductive particles inside it, making it a not-so-perfect conductor. I have also fabricated a simple dipole antenna using the wires made of the ...
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What material should I use for the plates of my homemade mica capacitors?
I recently acquired some mica as i want to build my own high voltage (50 kV if possible) capacitors. The problem I am encountering right now is that the surface of such a crystal isn't perfectly flat ...
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Finding free electron concentration to check authors' calculations for electron drift velocity
I am currently studying Practical Electronics for Inventors, Fourth Edition, by Scherz and Monk. Chapter 2.5.1 How the Shape of a Conductor Affects Resistance presents the following image:
I ...
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Main water line TDS measurement grounding
I am trying to implement a TDS sensor to measure a main water line connected pipe, with circuitry that is powered from the wall.
My TDS circuit is essentially a two electrode conductivity probe ...
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How do I find the resistive energy deposition of a flat braided aluminum?
I have a flat aluminum 6061, and the measured resistance is 0.5mOhms.
I have read that the resistive energy deposition is proportional to the action integral of the lightning current.
In the end, I ...
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How good is the Paracord 550 as an electrical insulator?
So following wikipedia the Parachute cord 550 is made from nylon Kernmantle rope, however this site where I sourced the cables from says that it is made of a Polyester sleeve (outer layer) and a core ...
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Can you effectively run lower power 5V TTL signals through a large piece of metal?
Is it possible to run a standard TTL signal through a very large piece of metal? For example, say 1-3 meters of metallic rebar?
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Are there any low temperature (60 - 100 degree celsius) soldering pastes?
I'm looking for low temperature soldering paste that doesn't come in a wheel of filament. It seems tin and bismuth soldering pastes have a melting point of around 160 degrees Celsius.
Are there any ...
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What material characteristics are most important for heating element material selection?
I want construct a heating element by screen printing a flat coil pattern of conductive paste onto an insulated substrate. This conductive paste consists of a powder of conductive metal contained in a ...
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Conductivity of liquids (3D resistor network)
Hi I'm an electrical engineer but have not seen this problem before. I'mn trying to measure/calculate the resistance of a liquid.
Background:
I'm working on an electronic device that can come in ...
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Which is a better conductor, a very thick rubber wire or a very thin copper wire?
I read somewhere that very thick wires are generally better conductors than very thin ones. Is this true? If yes, then would a very thick rubber wire be a better conductor than a very thin copper wire?...
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If my circuit is electrically isolated, do i have to worry about a polarizing effect on my sensor's output?
If I am making a conductivity sensor one of the things it need to watch out for is polarizing the water.
easiest way to do this is have the output output signal of the sensor have a +/-0.2V square ...
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Why is current rating for multicore cable lower than single core with the same cross section?
As per this resource, a single core 10 AWG (5.3 mm2) copper cable is rated for up to 52 amps, while the same cross section cable of 43 cores and more is only allowed to carry up to 15 amps.
Why is ...
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Why can my body conduct electricity from a 9 volt battery?
I've created a scenario represented identically in the attached image . My question is this:
When I connect Jumper 1 to my left hand and Jumper 2 to my right, the LED turns on very faintly but I feel ...
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Units of Conductance
I'm trying to understand how conductance that is measured in Siemens is equal
to Amperes/Volt.
The SI units of Siemens is given to be in $$ kg^{-1}m^{-2}s^3A^2 $$ (link).
I am not sure how this is ...
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I've become an electrical conductor for my headphones... but how?
So I have a pair of Bose noise-cancellation headphones that I plug into my keyboard every night to charge them (via my keyboard's USB port). My keyboard happens to be a metallic Apple keyboard. You ...
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Conductivity formula for Metals
Is there any expression for the direct change in conductivity of metals with temperature ?
I am aware of change in resistivity with temperature.
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