I need help with regard to this qns. I am supposed to use Thevenin theorem to find V aross the 8kΩ resistor.
Note that the voltage across the voltage source is 12V.
I broke the circuit after the 4kΩ resistor.
I am now trying to find V ab open circuit.
Since no current flows through 4kΩ, 2mA flows through 2kΩ resisor.
I across 6kΩ is (3k)/(9k) * 2mA = 2/3 mA
I across 3kΩ is 4/3 mA using voltage divider rule.
PD across 3kΩ is 4V.
PD across 6kΩ is 4V.
Here is my qn. If I take the loop across the 12V voltage src, my V ab open circuit will be 4V + 4V + 12V = 20V.
However, if I take the loop across the 6kΩ resistor, V ab open circuit is 4V + 4V = 8V.
Where have I gone wrong?
This problem is adapted from Basic Engineering Circuit Analysis 8th Edition.
Note that the voltage across the voltage source is 12V.
I broke the circuit after the 4kΩ resistor.
I am now trying to find V ab open circuit.
Since no current flows through 4kΩ, 2mA flows through 2kΩ resisor.
I across 6kΩ is (3k)/(9k) * 2mA = 2/3 mA
I across 3kΩ is 4/3 mA using voltage divider rule.
PD across 3kΩ is 4V.
PD across 6kΩ is 4V.
Here is my qn. If I take the loop across the 12V voltage src, my V ab open circuit will be 4V + 4V + 12V = 20V.
However, if I take the loop across the 6kΩ resistor, V ab open circuit is 4V + 4V = 8V.
Where have I gone wrong?
This problem is adapted from Basic Engineering Circuit Analysis 8th Edition.
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