How Do You Calculate Diode Current in a Circuit with Second Approximation?

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To calculate the diode current in a circuit with a 12V input, 2k ohm and 4k ohm resistors, and a 1k ohm load, the second approximation indicates the diode voltage is 0.7V. The Thevenin voltage is determined to be 8V with a Thevenin resistance of 1.3k ohms. The load current is calculated at approximately 3.17 mA, leading to a load voltage of about 3.17V and a load power of around 10 mW. The diode current is assumed to be the same as the load current if the diode and load resistor are in series. Clarifying the circuit configuration and the meaning of "second approximation" is essential for accurate calculations.
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1. So I have a voltage input of 12V, resistor 1 of 2k ohms, and resistor 2 of 4k ohms. These are connected to a diode and a load resistance of 1k ohm and load. I am instructed to use second approximation

2. The problem wants me to find load voltage, load current, load power, diode voltage, diode power, and diode current. I haven't had an issue with any except diode current.
3. I started by finding the thevenin voltage of 8V and thevanin resistance of 1.3k ohms
I found load current by subtracting VTH and 0.7 and dividing by the sum of RTH and RL. (~3.17 mA)
I found load voltage by multiplying IL and RL (~3.17 V)
Load power by IL * VL (~10 mW)
Diode voltage is 0.7V because of second approx.
Now, how do I find the diode current? My book seems to assume diode current is the same as load current. Why is that?
 
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Hi tgitgi, Welcome to Physics Forums.

Your problem statement is not clear for everyone. Note that we don't all have the benefit of being in the same class with you or having the same course materials to reference. So, Can you please:

1. Provide a better description of the circuit or (even better) post a circuit diagram?
2. Define what "second approximation" means.

(Note that if the diode and load resistor are series-connected then they must share the same current)
 
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Likes tgitgi and LvW
Your note answered my question. Thanks
 
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