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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Have I damaged my multimeter by applying voltage in resistance mode?
I have an VC97 digital multimeter. In resistance mode, I applied the multimeter leads to a battery with a 4.2V charge. I did this twice, and also did so in capacitance mode.
I didn't notice any ...
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Powering a device by USB?
I would like to power a device via the 5V USB port on a computer, because I will also be communicating with the computer via the USB data cables.
I know that USB ports provide 5V, but from what I've ...
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How is it possible that if I combine 100 Ohm resistors in different ways, I get _LESS_ resistance than original? [duplicate]
This is blowing my mind.
Let's say I've a bunch of 100 Ohm resistors, all identical.
How is it possible that if I combine them in parallel, I can get something that has less resistance?
Check this ...
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Find the Resistance between Two Terminals [closed]
Let's say R = 49 ohms, and we want to find Req between a and d, how do we do that? Do we have to find Req for the whole circuit?
user199242
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Equivalent resistance of resistors
Can somebody help me solve this. I need to find the equivalent resistance of these resistors. I really don't know where the trick here is. If somebody could help me I would really appreciate it
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Symbol of short circuit (or termination) with an Earth
Can someone explain to me why the symbol of the valve arrester has a short circuit, if it is already earth? I don't understand why it is depicted like this.
Why does the valve arrester have the symbol ...
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Fluctuation in resistance value
I'm trying to measure the resistance of a surgical screw that seems to have a low resistance, around maybe one ohm. I use a 1908P multimeter and wires having for resistance around 0.005 ohm.
Since ...
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Calculating the value of the resistance for controlling the speed of an AC fan
I have an AC fan whose speed I would like to control.
I had the idea of fixing 3 speeds with 3 switches, one for each speed: (25%, 50%, and 90%), and 3 relays. Each switch activates a relay and each ...
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Designing voltage summer without op-amp
The above circuit is from Operational Amplifier Adder.
Now remove feedback resistor and op-amp, and get the output. From the answer of the question, I know how the end result for Vout would be, ...
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Resistors and capacitors calculation for 555 timer circuit
I am new to electronics and I want to try an experiment.
I want to use a 555 timer to create an automatic food dispenser for my aquarium (something like opening a small door when the timer has ...
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Is equivalent resistance always lower if we add a resistor to a passive electronic circuit?
How to prove that equivalent resistance of any passive network is always lower (or equal) if we add a resistor between arbitrary two nodes?
Note that this is not necessarily a parallel circuit, 2 ...
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Resistance calculation [duplicate]
Are these resistors in parallel? A question is asked to find the equivalent resistance between X1 and X2; to my knowledge, these resistors are like parallel connections. But the choices are given as:
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Why does voltage reading increase the greater the resistance load?
I'm new to electronics. So basically I already understand Ohm's law and the math behind why this is the case. What I don't get is the idea behind it.
Shouldn't the greater the load resistance be, the ...
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Calculating voltage in a simple circuit
If I had a 12V battery and wanted to use an LED that used 2V and 20mA, then I need a resistor that will drop 10V and provide enough resistance to produce a current of 20mA.
Therefore I would use R=V/I ...
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finding output resistance of CB amplifier with ro
I have this CB amplifier circuit below
This is the small signal equivalent circuit arranged to find the output resistance R_out with the r_o included
Here is my analysis below to find the output ...
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