Questions tagged [charge]
A fundamental physical property held by various particles, most notably electrons
455 questions
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What do multiple volts mean?
"A joule (J) of work is done in moving a coulomb (C) of charge through a potential difference of 1V."
So does 2 volts mean: A joule of work is done in moving two coulombs of charge through a ...
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understanding capacitor in a circuit 40106 Schmitt trigger
I have the following schematics that consists two 40106 Schmitt trigger circuits. The left hand side one has bigger capacitor then the right hand one.
I know that the right hand one will oscillate 10 ...
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Battery charging slow
I have 2 batteries connected in series (each battery rating - 3.3V and 5Ah). So the combine effect after connecting in series is 7.3V 5Ah (practically getting 7.56V in the battery)[the battery has ...
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Resistances to two batteries where the bat1_pos + bat1_neg = bat2_pos + bat2_neg? But, bat1_pos is shorter than bat2_pos
SOK makes a unit called "12-Slot Outdoor Insulated Battery Rack – Fits SOK & EG4 Batteries"
In this configuration there are two batteries next to each other stacked six sets deep. Both ...
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Can I integrate \$v_y(y) \$ in Meyer model for MOSFET? [closed]
$$
I_D = -W \cdot Q_N(y) \cdot v_y(y)
$$
Re-write equation in terms of voltage at location y, V(y):
$$
v_y(y) = -\mu_n \cdot E_y(y) = \mu_n \cdot \frac{dV}{dy}
$$
$$
\Rightarrow
\int dy = \int \mu_n \...
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How is channel charge calculated in meyer model?
The following is from MOSFET Circuit Models.
$$
q_N^v(v_{GS}) = -w \int\limits_0^L C_{ox}^c(v_{GS} - V_{Tn} - v_C) dy \\
$$
Recalling that current is related to the electric field
$$
\begin{align}
dy &...
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MOSFET Total Gate charge graph (Qg)
Below is a Vgs -Qg graph of the IXTH88N30P N-channel MOSFET.
Datasheet: https://www.mouser.com.tr/datasheet/2/240/media-3322045.pdf
As seen in the graph, this curve is given for Vds = 150 V, Id = 44 A ...
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What type of device is this on TP5000 Application Exapmle?
Data Sheet (Chinese)
Question 1
Component N1 looks similar to a mosfet but doesn't look like other ones that I have seen for N-Channel. What is this component supposed to be? This example is for LFP ...
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Charge "something" over a 10 second interval then dump the charge on a load. (Alternative to battery?)
I'm getting a limited current of about 10 mA from a 12 V DC source. I would like to charge "something" (anything but a battery) with this energy over 10 seconds, and then dump it to a 12V ...
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Piezoelectric Disk Charge Generation and Detection
I have a piezoelectric disk. I am trying to determine the sensitivity of this disk for the sake of making a charge model more accurate. The charge model in question:
I have attached the piezoelectric ...
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Why is capacitor equilibrium based on balanced voltages and not balanced charges?
The problem below is from the electrical circuits chapter of Essential University Physics Volume 4. I am having trouble understanding the essential idea behind the solution.
I initially tried solving ...
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Estimating lithium-ion battery run time at different voltages
A polymer lithium battery in a powerbank (marketed as 30,000 mAh / 3.8 V, 114 Wh), has an actual electric capacity of 19,944 mAh, and an energy capacity of 104 Wh as measured with a constant load ...
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Signal conditioning of a piezoelectric sensor
I am currently working on a project that involves the use of a piezoelectric sensor which is of the ceramic type and produces charge when a force is applied. I want to convert this charge to a voltage ...
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To what voltage will this capacitor charge?
To what voltage will the capacitor in the circuit here above charge?
The circuit is fed by 10V DC.
I=U/R=10/100k=0.1mA
Voltage drop on the 10k is 1V.
Will the capacitor charge to 9V or to 10V?
Someone ...
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How is the total gate charge of a MOSFET affected by the temperature?
For P- and N-MOSFETs, Vgsth will decrease (in absolute value) when the temperature rises.
What is the impact of the temperature on the total gate charge for P- and N-MOSFETs?
What is the order of ...
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Engine instrument panel with duplicate Charge light, one incandescent and the other LED [closed]
I have an engine in a boat. The ignition on switch, start, and heat are on a panel on the navigation desk. There is also a power LED, incandescent charge, and led oil light. All the engine instruments ...
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Can I charge laptop with wire 20awg
My laptop has a maximum power is 170W, 20V, and I often use it with max power.
My adapter has a broken power jack and I must change the wire that supplies power for the charge.
I use wire 20awg, the ...
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Why are smoothing capacitors useful/why do they work
Okay so from my understanding and looking at the equation for the impedance a capacitor has, the high frequency signals would be relatively easy to be sunk to ground (if the capacitor was grounded) ...
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Using two TP4056 modules to charge two cells in series
Here's an attempt to get use two modules of charges to charge and protect each of its own batteries connected in series.
Adding back-to-back P-mosfets and a shottky diode converts the whole system ...
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Calculate capacitor charging constant time connected to battery and boost converter
I know the formula to calculate the constant time for capacitor is t=RC and for full charge t=5RC.
In the following example there is not resistor in the circuit but of course we are not in the ideal ...
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Designing a Charge Amplifier Circuit in PSpice for Piezoelectric Sensor
I'm new to using OrCAD PSPICE 16.6 and need some help. I'm trying to design a charge amplifier for a piezo sensor before building the actual circuit. I've chosen a VSIN source as my input to represent ...
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What is the charge stored in the equivalent capacitance?
Three capacitors C1, C2, and C3, whose values are 10 µF, 5 µF, and 2 µF respectively, have breakdown voltages of 10 V, 5 V, and 2 V respectively. For the interconnection shown, the maximum safe ...
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Delay-Free Switched-Capacitor Integrator Difference Equation Derivation
I want to derive the difference equation of a delay-free SC integrator using charge-domain analysis.
Here's the example I am following. This shows you that for charge domain derivation, all you need ...
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Will the laser beam of a laser printer make the OPC drum more positively charged or more negatively charged [duplicate]
while I was tutoring students about A LEVEL computer science in chapter 3 -- hardware, I found a very interesting question about printer.
Some websites say that the laser beam could remove charges on ...
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Why is resistance (inversely) proportional to area instead of circumference?
TL;DR From the Veritasium-vs-ElectroBOOM debate about the 1 m / c question, it seems to me that most properties about conductors depend only on surface charges. So shouldn't quantities like resistance ...
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Propagation speed and capacitors charging speed of transmission line
I am a bit confused on the speed of voltage propagation in the transmission line and I hope someone can enlighten me. I understand the speed of step up voltage propagation is in the same order as the ...
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Electric field of line charge and coaxial conductor
I'm currently having trouble understanding why the electric field inside a coaxial conductor (assuming that the charge is evenly distributed on the inner and outer conductor and opposite signed) is ...
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Using an RC delay circuit on a MOSFET Gate
I have 24v Input from push button, I want to make delay when I leave the button and the PMOS will stay on for about 0.6sec.
Attaching some timing diagram for the required operation signals (pay ...
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Strange capacitor charge / discharge oscillations - SPICE
With this setup
ngspice produces, for an 1ms dip-to-zero spike, this output
Voltage source
pwl(0 15 1m 15 2m 0 3m 0 4m 15 5m 15 2 15) r=0
If I make ...
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Solar panel help
I already have a solar charge controller connected to my solar panels protecting the attached batteries from overcharging.
However I'd like to charge a second battery bank without connecting it up to ...
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DS3231 module li-ion charging circuit tweak
Most of the DS3231 modules come with a "charging" circuit for a LIR2032 battery. I understand that, as-is, it's considered garbage.
The reason people say not to use the module as-is is due ...
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Transient Charge Density in Conductor
Veritasium's (Derek Muller's) video How Electricity Actually Works makes the claim at
4:44 that:
The truth is, if you average over a few atoms, you find the charge density everywhere inside a ...
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The two capacitors are in series but positive end of one plate is connected to positive end of the other
Like the title says, my task is to find the initial voltage across the terminals. The two capacitors are in Series with positive end of one plate connected to that of another.
The given information ...
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Calculating charge current of a bypass capacitor, choosing series resistance
I'd like to switch power supply of two sensors, each of them with a bypass capacitor at their supply pin, with an ATmega328P MCU output pin with an absolute maximum rating of 40mA.
The sensors ...
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Optimize a design for current/charge oscillator
I'm trying to understand how to design a circuit that cycles charges between two capacitors between cycles. Basically I want a large positive current pulse into one cap at the same time a large ...
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Transformer in a 2-3A charger
I have opened one of my phone charger to check the transformer used to provide an output of 2-3 A. I am a bit surprised regarding the size of the transformer. It is very small and the wires in the ...
user340506
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How is charge limiting achieved in laptops? Why does it cause heating when limit is reached?
Laptops have this feature which allow you to limit battery charging to up to a certain percentage.
Electronics wise, how is this charge limiting achieved? Is there actually a proper relay cutting off ...
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Cheap China solar water pump kit only runs for 10 minutes [closed]
I checked everything with a multimeter, everything seems fine. The batteries charge to full capacity. The output from the solar panel seems correct. The output from the controller seems correct.
In ...
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Charge on capacitors in circuit
I have this circuit with defined components specifications:
R1 = R2 = R3 = 100 kΩ
C1 = C2 = 1000 μF
C3 = 4700 μF
U = 24 V
First question is to calculate the charge on each capacitor. I managed to do ...
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What is the total charge Q of 1 m³ of copper?
I was wondering if I can calculate the total charge Q of 1 m3 of copper, see my calculation in the picture below. Is this correct?
The correct solution (thanks to the community in the comments below):...
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Calculate potential between two rods
Suppose we got four thin, long and parallell conductors with charges shown in the image below. Each conductor has a radius \$ r\$ and length \$ l\$ . Our problem is to find the potential between the ...
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Why does a smaller capacitance equate to a larger voltage drop physically?
I was hoping someone could explain practically/physically why a smaller capacitance has a larger voltage drop than a higher capacitance. The equation is V=Q/C, so based on that it's very easy to see, ...
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How to make parallel piezoelectric/PVDF transducers for force measurement?
I am having difficulty in understanding a concept since I am not in the electrical field. I am working on a project to measure the dynamic force on a surface using embedded PVDF transducers. Based on ...
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Making a powerbank using lead-acid batteries [closed]
I have three 12 V, 12 Ah deep-cell lead-acid batteries wired in series that were used for a scooter. I’d like to repurpose this battery pack into a powerbank that can be used to charge electronic ...
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Is this charge pump analysis correct?
Assume switch on resistance is 0. Also assume that phi1 and phi2 are non overlapping clock signals and that the initial condition of all caps is 0V.
My final answer suggests that Vout/Vin is 2 only ...
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Reasons to use charge amplifier?
Here are some preliminary information before asking the question:
When piezoelectric force sensors are subjected to a stress, they
produce a charge that is proportional to the force. The amount of
...
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What's the difference between electricity charge and signal?
To better understand the difference between electricity charge and signal, I would like to know in which kind of case is electricity charges actually used, and in comparison, in which kind of case is ...
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Which drains first when connecting Battery A -> Battery B -> Load? [closed]
I have two large commercial USB batteries I need to combine to produce power for a 10hr period. Each alone can power my load for ~6-8 hours.
Reading a few other articles:
Can batteries be charged and ...
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RS310 DC power supply charging 12 volt car battery
I am trying to charge a car battery with a Rockseed RS310P power supply. I set the voltage to 14.5 V and the amps to 2.0 A but when I connect it to the battery and turn it on the current drop to a ...
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Battery capacity evaluation
To measure NiMH battery capacity, everything I've read so far indicates that in order to get an accurate evaluation you have to measure the discharge parameters.
I can understand that, however in my ...
