# Tagged Questions

117 views

### What is Kirchhoff's voltage law all about?

what is the Kirchhoff voltage law ? isnt it the sum of potential drops as we move along a circuit till the same point should be zero it is simply energy conservation law that when the battery ...
78 views

### Determining resistance per load with only power and volts

I have a extra credit problem in my class and I'm slightly stumped as to where to go next after I determine the It, Et and Rt. I am starting with a total power of 2 watts and 32 volts. I know to get ...
135 views

### Behavior of capacitor with infinite capacitance at steady state (DC analysis & AC Analysis)

What is the behavior of the capacitor below at steady state (DC/AC Analysis)? simulate this circuit – Schematic created using CircuitLab
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### Reading Voltage NTC Sensor, Unexpected Behaviour

Below pictured is the basic circuit im working with, NCT is apparently pretty much a variable pot resistor. The measuring point ive added. According to the manual for my car, the sensor is provided ...
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### Potentiometer voltage change

I'm trying to understand simple things about electricity reading allaboutcircuits.com web. This chapter includes image which´s principle I don't understand. Here it is: When supplying constant ...
203 views

### Why does the voltage changes in this simple circuit?

I'm beginning to learn electronics, and there's something I just can't grasp. I was told that a high resistance in a circuit would lead to a smaller current passing through it, but the voltage would ...
280 views

### Overcoming a wire's internal resistance?

Let's say I have a very sensitive device that needs EXACT voltage. Let's say that the voltage it requires is 5 volts. Now let's say I'm running the aforementioned voltage over a wire with an ...
1k views

### If voltage is measured between two points on a wire, with no resistance in between is the voltage zero?

I have a series circuit. Let's say the battery has a potential difference of 10 Volts. On two points of the wire before the current hits any resistors, I attach ...
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### Small-signal input and output resistances of the circuit

I am given this circuit: And I am trying to determine the small-signal input and output resistances. I was either given or found all the following info for the circuit: VA = 110V β = 115 T = ...
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### How to find τ in these circuits?

I know that $τ = \frac{L}{R}$, but what is $R$ in this formula? It seems to be the total resistance, but how to find it in the schematics?
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### basic math question about voltage, ohms, resistance

total n00b here. After working on several projects by copy & paste from other people's schematics and code, I'm finally digging in and learning some of the math to know what I'm doing. If I have ...
118 views

### Is is possible to produce a resistance that represents the average of two thermistors?

For example, if I want to connect 2 thermistors to a thermostat in a circuit and then return the average resistance between the two of them to the thermostat's ADC.
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### Voltage distribution between components

I often see the same method for computing voltage distribution in electronic circuits implying components whose V-I curves are not trivial. For example, in a circuit implying a resistor and a LED ...
193 views

### Mathematical approch to measuring current, voltage and resistance of mixed series and parallel

If there is a circuit like the one below, where all resistors are 1k ohm, how does one determine the currents? The voltage sources are all 10 volts. The problem I am having is that I do not know if ...
1k views

### Why do diodes have a voltage drop?

Is resistance what makes a diode have a voltage drop? Or is it impedence? If it is electrical energy being converted to light, please tell me what this effect is called.
2k views

### Potential difference across one resistor with and without a known current?

Okay imagine you have a voltage supply of 10V and one Resistor of 5 Ohms. Now find the current : I=5/10 = 0.5A So potential difference across that resistor : V=IR=10V .. which proves this statement ...
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### Help with understanding Current, Voltage and Resistance

Is my analogy correct: With a highway as an example, would Resistance (ohms) be the number for lanes in one direction Current (amps) be the density of cars on the road Voltage (volt) be the speed ...
3k views

### How to calculate current and voltage draw of a single resistor circuit?

If I have a single 270 ohm resistor connected in a circuit to a 3.3V 50mA power supply, how can I measure the voltage and current for the resistor? I'm familiar with Ohm's law V=IR, where V is the ...
513 views

### How does audio get transmitted from my iPod to speakers?

I need some help understanding a simple concept. I understand that my iPod/any other audio device sends electrical signals to my speakers/headphones. From my research so far, an analog signal is ...
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### Understanding electric power

While in a mood to purchase a Peltier strip, I visited the amazon page which stated the specs of a Peltier thermoelectric cooler, one stated 12 V and 92 W and other one stated 12 V and some 77 W. As ...
324 views

### MOSFET sub-threshold operation

I have a question related to the sub-threshold operation of MOSFETS. Let's say I have the following setup: How can I calculate the sub-threshold current ( Id when Vgs < Vgs(th) ) at Vgs = 0.5V ...
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### How does the electricity “know” the ratio of the resistance in a voltage divider?

I'm having a hard time conceptualizing what/how things are working in a voltage divider setup. I've read a couple other questions/explanations where the answerer has said to "not think about it in ...