Tagged Questions
0
votes
2answers
177 views
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 ...
1
vote
2answers
94 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.
5
votes
2answers
88 views
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 ...
-6
votes
2answers
150 views
Battery with most mAh that outputs between 1 and 1.5v? [closed]
I am looking for a rechargeable battery between 1 and 1.5 volts that can provide this voltage for the longest amount of time (most mAh). Any suggestions? Thanks.
3
votes
2answers
143 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 ...
6
votes
3answers
369 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.
0
votes
2answers
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 ...
2
votes
5answers
554 views
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 ...
1
vote
1answer
2k 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 ...
1
vote
2answers
253 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 ...
4
votes
2answers
225 views
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 ...
0
votes
1answer
265 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 ...
5
votes
8answers
1k views
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 ...
5
votes
2answers
236 views
What would the current be if I plug an LED into a perfect circuit
If I had an LED that had a forward voltage of 2.2 volts with a forward current of 20mA and I somehow created a battery that was exactly 2.2 volts and I put that LED, and only that LED, on that ...
3
votes
2answers
4k views
5V to 3V, calculate resistor value (or use diode?)
I want to connect this dv motor to the 5V output of an Arduino board. Of course I need to get the 5V down to 3V in order for the motor to function correctly. I've read that I could use a diode with ...
