Solve the Circuit: Find v(t) Over Inductors

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AI Thread Summary
The discussion focuses on calculating the voltage v(t) across two inductors in a circuit with given initial currents. The user initially calculates v(t) as 1440 e^(-600t) based on a total current of 30 amps and a resistance of 48 ohms. However, they express confusion over the book's answer of -1440 for the coefficient, questioning why it would be negative given the direction of current flow. The user believes that since both currents flow in the same direction, the voltage should be positive at the top and negative at the bottom. Clarifying the sign convention for voltage across inductors is essential for resolving this discrepancy.
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Homework Statement


http://img134.imageshack.us/img134/8382/circujitqt7.th.jpg

i0(0) = 10 A
i1(0) = 20 A
The currents through the inductors flow from top to bottom. And v(t) is + on top and - on bottom

Homework Equations


The Attempt at a Solution



Find the voltage v(t) over both inductors.
Since the current going through both inductors is 30 amps total, I get 30*48 ohms
v(t) = 1440 e^(-600t) [\tex]<br /> unfortunately, according to my book it&#039;s -1440 for the coefficient, what am I doing wrong?<br /> I really don&#039;t see why it would be negative, both of the currents are flowing in the same direction
 
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The current going through the resistor is going from bottom from top. So the bottom must be more positive than the top
 
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