# Homework Help: Learner what is resistance value here.

1. Jun 20, 2012

### zakki

hello people,

in this circuit the voltage be 50 millivolts and R2 is 5 gigaohms how much should be R1 and R3 so that my output current is 10 picoAmps.

regards,
zakki.

#### Attached Files:

• ###### Untitled.png
File size:
3.2 KB
Views:
135
2. Jun 20, 2012

### psparky

Show a little work or thought before we help....

3. Jun 20, 2012

### zakki

getting a small doubt with the resistors,
which are parallel and in series?
can you tell me the total voltage please?

4. Jun 20, 2012

### phinds

You are not listening. As psparky said, you need to show some work on your own before you get help here.

It is against the forum rules to just spoon-feed people answers to homework problems. Please read the forum rules.

5. Jun 20, 2012

### zakki

brother,
just tell me which are in parallel and which are in series thats it.
i will do the rest of it.

6. Jun 20, 2012

### DailyDose

You need to follow the nodes. Always best to redraw the circuit in a manner that is "more obvious" to you. And like I said, this is best done by following the nodes. KVL should give you the answer. However, make sure you've drawn the circuit correctly.

7. Jun 20, 2012

### psparky

I'll give ya some hints.......

Step 1.

What voltage do you need at the blue node to find your desired current. Use V=IR.

Step 2.
Pick a value for R3. Now use voltage division to find your last resistor value...using the voltage you just found at the blue node.