# Homework Help: Finding the values of resistors

1. Sep 28, 2013

### ZeeAngel

1. The problem statement, all variables and given/known data
In the problem i have to find the values of resistors using voltage divider, and use KVL to determine the currents.

2. Relevant equations

Vi= [Ri / (R1+R2+...+Rn)] * Vs

1/Rtotal = 1/R1 + 1/R2 + ... + 1/Rn

Ʃrise + Ʃdrop = 0

3. The attempt at a solution

In order for us to use voltage divider the resistors must be in series.

Req = (40*R2)/(40+R2), but we still don't know the resistance of R2.

However, later I tried to use the KVL equation to find the voltage for Req.

-24+8+Veq = 0 → Veq = 16 V

Then I used the voltage divider equation:

Veq = [Req / (R1 + Req) ]* Vs // but again we have two unknowns here again

And that's the point where I stuck, I know this problem is trivial but my brain cannot come up with anything else to solve this.
1. The problem statement, all variables and given/known data

2. Relevant equations

3. The attempt at a solution

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2. Sep 29, 2013

### rara

Using KVL, we know that Veq=24V-8V=16V. Using Ohm's Law, we can easily get R2=16V/1.6A=10 Ohms. The rest is obvious! :)

3. Sep 29, 2013

### ZeeAngel

Thank you very much :D