How Do You Calculate Resistance in a Series Circuit?

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To calculate resistance in a series circuit, the total resistance is determined using Ohm's Law, where 300 mA equals 9 volts divided by resistance (R). The total resistance is found to be 30 ohms, suggesting that if there are two resistors of equal value, each would be 15 ohms. There are questions regarding the accuracy of the circuit representation, particularly the inclusion of inductors without a switching mechanism. Clarification is needed on whether "2R" refers to two resistors of the same value or a single resistor labeled R2. The discussion emphasizes the importance of correctly interpreting circuit diagrams for accurate calculations.
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_________300ma__
|...... |
|...... ∏ L1
_ +......| R1
9v......|........ ignore the dots in the middle
- -...... ∏ L2
|......| 2R
|________________|

Find the:

The value of R

The total resistance

and any other answers this question might yield

Thanks a lot.

only question i got wrong in a test. :(
 
Last edited:
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300ma = 9/R
Total Resistance = 30Ohms

30/2 = 15ohms each resistor?
 
lazyboy92 said:
_________300ma__
|...... |
|...... ∏ L1
_ +......| R1
9v......|...... ... ignore the dots in the middle
- -...... ∏ L2
|......| 2R
|________________|

Find the:

The value of R

The total resistance

and any other answers this question might yield

Thanks a lot.

only question i got wrong in a test. :(
I am redrawing the circuit, hopefully this is easier to look at:
Code: 
 ________300ma__
|               |
|               ∏ L1   
_ +             |  R1      
9v              |
- -             ∏ L2
|               |  2R
|_______________|

Are you sure you reproduced the question accurately? It's weird to have those inductors in there, without for example a switch that closes at time t=0 or something along those lines. Also, is the 300 mA the current at some specific time, or after a long time has passed?

Also, did you mean to say 2R or R2 in the figure?

drkidd22 said:
300ma = 9/R
Total Resistance = 30Ohms

30/2 = 15ohms each resistor?
If R were 300 ohms, then the current would be 9/300≠0.3A.
 
Last edited:
Redbelly98 said:
If R were 300 ohms, then the current would be 9/300≠0.3A.


I mean 30 Ohms, the O makes it look like a 300
 
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