# Value of Resistor in Circuit

Discussion in 'Homework Help' started by electronic_engineer, Aug 10, 2016.

1. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
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What Value of R should be used in Figure if it is required that the voltage across R be 36V?

2. ### Jony130 AAC Fanatic!

Feb 17, 2009
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But first you need to show us your attempt.

3. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
10
1
As the voltage across R is needed to be 36V , similar will be voltage across 6KOHM resistor, so 6m Amp would be current through it,

If I know about the total current drawn from voltage source , I can, then, know the current through R resistor by current division principle, but I dont know the total current. Or if I know the value of R then combining R in parallel with 6K ohm resistor and then adding the equivalent with 2Kohm and 4Kohm, in this way I can get the current drawn from voltage source, but value of R is required and total current provided by voltage source is not given, how can I solve now?

4. ### Jony130 AAC Fanatic!

Feb 17, 2009
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But you know the voltage drop across 2kΩ resistor and 4kΩ resistor. Is this information not enough ?

5. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
10
1
How can I know the voltage drop across 2Kohm resistor and 4Kohm resistor?

I only know that voltage drop across both will be 90-36 V, but what will be voltage across each 2Kohm and 4Kohm individually? How can I know that when I don't know the current through them?

6. ### Jony130 AAC Fanatic!

Feb 17, 2009
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But 2kΩ and 4kΩ resistor are connected in series. So you know the current, right?

7. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
10
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They are in series but 6Kohm resistor in parallel with R ohm is also in series with them when I dont know the value of R , how can I calculate current?

8. ### Jony130 AAC Fanatic!

Feb 17, 2009
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Do you know that in series circuit we have the same current ? Also we already know the voltage drops across 2kΩ and 4kΩ resistors.
So we can find total current.

9. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
10
1
Yeah , now I got it , thank you so much really I made such an stupid mistake

Last edited: Aug 10, 2016

Aug 2, 2016
10
1

11. ### Jony130 AAC Fanatic!

Feb 17, 2009
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I'm glad that I could help.

12. ### DGElder Member

Apr 3, 2016
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Don't blame it on your parents.

13. ### electronic_engineer Thread Starter New Member

Aug 2, 2016
10
1
Typing error in excitement

Jony130 likes this.
14. ### DGElder Member

Apr 3, 2016
347
87
Yes I got that