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Does the voltage drop across the internal resistance when charging?

ByLeezer

And more precisely, if polarization effects in an equivalent circuit are also taken into account… does the capacitor remain charged when charging or does its charge drop like when the current flow stops? So if a charger is connected to the terminals, directly after discharging or even during discharging, then the capacitor discharges immediately and…

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ByMrVerbrecher

Can someone help me solve this task?😅 "A sculptor creates a small bronze statue that weighs 1.2 pounds. She plans to create a version that will be four times larger in every dimension. How much will this larger statue weigh if it is also made of bronze?" The task is actually in English but I…

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Transistor3055
Transistor3055
1 year ago

Minimum position of the pot (at 0%):

The smallest voltage at the MP3 should be 2V. It’s the voltage over R3.

R3 is 1 KOhm tall. Calculate the current I3 which flows through R3.

The formula I=U/R is hopefully known.

U3 = 2V and R3 = 1 kOhm

I3 = U3 / R3 = 2V/1KOhm = 2mA

It is a series circuit, the current I is equal everywhere. I3=I2=I1=I=2mA.

Maximum position of the pot (at 100%):

Now 4V is to drop across R2 and R3 together.

U23 = 4V and I=2mA

R23 = U23 = 4V/2mA = 2kOhm

R23 = R2+R3 | now switch to R2

R2 = R23 – R3 = 2kOhm – 1KOhm = 1KOhm

Now calculate R1.

R1 = U1/I

U1 = Ug – U23 = 5V – 4V = 1V

R1 = U1/I = 1V/1mA = 1KOhm

Ready!

Good luck!

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Mointer
Author
Mointer
1 year ago
Reply to  Transistor3055

How do you know the U3 2V?

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Transistor3055
Transistor3055
1 year ago
Reply to  Mointer

It is the voltage at setting 0% of the pot.

If the poti stands at 0% (minimum) it is a voltage divider

  • R1 + R2
  • and R3

If the pot is at 100% (maximum), it is a voltage divider

  • R1
  • and R2+R3

If you ever draw a circuit diagram for the power position 0% and for the power position 100%, then it becomes clearer.

Read the question at 0% to be 2V at MP1. This is the voltage on R3.

Good luck!

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Transistor3055
Transistor3055
1 year ago

If you think R3 has 2 volts with 2V over R3

That’s it.

or that between R2 and R3 are still 2V

YES, R2 also has 2V

or what do you mean

The pot can be set. At 0%, the tap is exactly at the connection “R2, R3” of this node is at 2V g. GND. On the other hand, at 100%, the tap is exactly at the connection “R1,R2” of this node is at 4V (2V+2V). GND. GND? I’ve explained downstairs.

and I also do not mean that the voltage at the measuring point MP1 is adjustable against GND in the range of Ump1 2V-4V

The MP1 can be “shifted” with the help of the pot, from 0% to 100%. The question only describes these two extreme values.

GND means ground (also called mass). Thus, the reference point to which all voltages are specified or measured. In this case, it is the negative pole (-) of the supply voltage. A voltage must always be measured between two points. The GND (=Masse=Minuspol) is one of the common reference points to indicate a voltage. At the positive pole, for example, is “+5V”, which means the voltage between plus pole and mass(=GND=minus pole) is 5V.

Conclusion: If you use GND or mass in the description/description, you can “write” a voltage at any point of the circuit. It simplifies the description. No voltage arrows are then required in the circuit diagram, since GND is always defined for these voltage indications.

Conclusion: The circuit diagram is clearer without voltage arrows, because GND is thus clearly defined.

Good luck!

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Mointer
Author
Mointer
1 year ago

If you think that R3 has 2V over R3 or that between R2 and R3 are 2V or what do you mean that exactly and I also do not like that in the task position with the voltage at the measuring point MP1 is adjustable against GND in the range of Ump1 2V-4V

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Transistor3055
Transistor3055
1 year ago

… our instructor did not understand this task

Then you can learn nix with this instructor. These are very simple basics, this should master the instructor!!! I’m sorry he can’t explain it.

I repeat: Draw a circuit for the potency 0%.

It is a series circuit of 2 resistors (R12 and R3)

R1+R2 is the first resistance the series connection, call it R12.

R3 is the second resistance R3.

Now you can use the known sizes 1k (means 1 KOhmand 2V via R3 calculate the current through this series circuit. The current in a series circuit is always equal everywhere!

Here is a series connection (=one Unloaded voltage divider), here explained:

https://www.elektronik-kompendium.de/sites/slt/0201111.htm

Subsequently, a further circuit for potting is shown 100%: ….

etc. see my description above ….

Good luck!

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Mointer
Author
Mointer
1 year ago

Does this mean that the 2 or 4V at the R3 still have to fall off? Or do I still misunderstood our instructor has not understood this task

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