Find current using KVL (with dependent source)

AI Thread Summary
The discussion focuses on applying Kirchhoff's Voltage Law (KVL) to find the current using dependent sources in a circuit. The user initially calculated the current Ix as 2 mA but expected it to be 1.5 mA, prompting a request for help in identifying the error. After reviewing the equations, it was determined that the mistake was in not properly accounting for the unit conversion of Ix from mA. The corrected equations were confirmed, leading to the resolution of the problem. This highlights the importance of unit consistency in circuit analysis.
iharuyuki
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Homework Statement


upload_2015-4-15_22-24-13.png


Homework Equations


V = IR
Kirchoff's Voltage Law

The Attempt at a Solution


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Top loop - a
Bottom right - b
Bottom left - c
Ix = x

KVL:
top: a(6000) + (a-b)(2000) + 5x - 10=0
bottom right: -5x + (b-a)(2000) + b(3000) + (b-c)(4000) = 0
bottom left : 10 + (c-b)(4000) + c(2000) = 0
x = -c

x comes out to 2 mA when it should be 1.5. Where did I make a mistake?

Thank you very much.
 
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How did you account for the given detail that ##I_x## is in mA?
 
got it! That was the error. The proper equations were this:

a(6000) + (a-b)(2000) + 5x - 10=0

-5x + (b-a)(2000) + b(3000) + (b-c)(4000) = 0

10 + (c-b)(4000) + c(2000) = 0

x/1000 = -c

Thank you very much!
 
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