Arduino Question 1

Start with the branch furthest from the voltage source. Add the series resistors together, 1k+1k+500= 2.5K  then add the next branches series resistors together. 1k+3k=4k. Those two branches can then be added in parallel, 1/(1/2.5k+1/4k)= 1.53k then parallel add the last branch  1/(1/10k+1/1.53k)=1.33k. Now you can find total current with ohms law,  i= v/r, I=5/1.33k=3.75mA. Since you know the total current now you know that the sum of each branch has to add up to that. Every branch will have 5 volts across it, so now you can solve the individual branches with ohms law. I'm not sure why you have a short across the 1k resistor in your circuit, but you can just take it out of the equation. If that's part of your equation.

Maybe I miss understood the problem. You have 3 branches, and you'll have i1=i2=i3 so divide 5.08mA / 3 to get the current in each branch. You'll get 1.69mA. Use ohms law to find the resistance of each branch, r=v/I, r =5/1.69mA= 2.95k. Now make the series resistance of each branch = 2.95k. Check this circuit: http://everycircuit.com/circuit/6122239142133760

I was right

Although this is a parallel circuit with 2 mixed circuit configuration you can see that the voltage is 5V and that the first three resistors has 5V then of course because because of the in serie resistor configuration you get a voltage drop in between them. But that doesn't mean that the current is different because that will in a series configuration stays the same. How amazing is electrical engineering. So I1=I2=I3 which is 500 micro Amp.

Im sorry, i still don't understand what your are saying with i1=i2=i3 which is 500 micro amps. The only branch that has 500 micro amps is the fist one with the 10k resistor. The other two branches have different currents.

Dear alexpu, thank you for your comment. Your example circuit is exactly what I had to do. You have I1 which is 5V/10k ohm which has 500 micro Amp. Then you have to choose the correct resistor

https://create.arduino.cc/edu/courses/local/quiz/question.php

Alexpu check the circuit now I have adjusted it

@Jossver no problem, I'm glad I could help. 👍

alexpu what is your background ( I know something with electrical engineering). Are you an engineer?

I am a second year electrical engineer student

No, just a tech. Good for you, do you like it so far?

To be honest Alexpu, it's nice to study electronics. The danger is however that a lot of students think they are an engineer because of study. Somehow it is sometimes better to be a tech as you get a true feeling of electronics and get your hands dirty. I think that is better to truly understand electronics instead of reading books. That's why I bought everycircuit to have a kind of simulation experience of feeling what electronics is doing.