Maximum power of circuit with dependent voltage source

AI Thread Summary
The discussion focuses on solving a circuit problem involving a dependent voltage source, using equations for open-circuit voltage (V(oc)) and short-circuit current (I(sc)). The user attempts to find the Thevenin equivalent resistance (R(th)) and voltage (V(th)) but encounters a discrepancy in their calculations, specifically a 1 kOhm difference from the expected answer. They provide equations for both the left and right loops of the circuit, ultimately calculating I(sc) as 0.2 mA and R(th) as 2 kOhm. The user seeks clarification on the error in their solution process. The discussion highlights the importance of accurate circuit analysis in determining dependent source values.
iharuyuki
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Homework Statement


upload_2015-4-16_7-58-20.png


Homework Equations


V(oc) = I(sc) * R(th)
Kirchoff's voltage law

The Attempt at a Solution


a) is okay. For part b):

After redrawing with the R(th) and V(th) found in part a):

Equations of loops:
s is I(sc)
a is I(left loop)

left loop:
-8 + a(4000) + (a-s)(4000) = 0

right loop:
(s-a)(4000) - (2000)x = 0

I(x):
a-s = x

I(sc) comes out to 0.2 mA
Then V(oc) = I(sc) R(th)
4 V = (0.002 A) R(th)
R(th) = 2 kOhm = R(L max)

However, this is 1 kOhm off from the answer.

What is the problem with the above working?

Thank you very much.
 

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All is good, thanks!
 
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