## characteristic equation

1. The problem statement, all variables and given/known data

im trying to find the characteristic equation of a circuit with a current source and 3 elements all in parallel: a resistor and 2 inductors L1 and L2.

2. Relevant equations

i believe the current can be calculated as:
i(t) = v(t)/R + iL1(t) + iL2(t)

3. The attempt at a solution

is this anywhere close?
(1/R)dv/dt + 1/L1(v) + 1/L2(v) = 0
i guess i don't understand what is equated in a characteristic equation.
 PhysOrg.com science news on PhysOrg.com >> City-life changes blackbird personalities, study shows>> Origins of 'The Hoff' crab revealed (w/ Video)>> Older males make better fathers: Mature male beetles work harder, care less about female infidelity
 combine L1 and L2 in parallel into L_total (assuming you don't care mutal inductance), now you have one less component.
 Recognitions: Homework Help Is the current source a constant source or one of a function of time? And how could you write iL1 and iL2 as though the two i's for both are the same? Is it given that the inductance of both are the same?

## characteristic equation

 Quote by losafojjog 1. The problem statement, all variables and given/known data im trying to find the characteristic equation of a circuit with a current source and 3 elements all in parallel: a resistor and 2 inductors L1 and L2. 2. Relevant equations i believe the current can be calculated as: i(t) = v(t)/R + iL1(t) + iL2(t) 3. The attempt at a solution is this anywhere close? (1/R)dv/dt + 1/L1(v) + 1/L2(v) = 0 i guess i don't understand what is equated in a characteristic equation.
Unless your current source is a constant, its derivative is not zero. If the source is constant, both inductors will act as short circuits, so there is no voltage across the resistor and no dynamic equation.
The characteristic equation is the algebraic equation you obtain when you apply the Laplace transformation to your differential equation.

 Similar discussions for: characteristic equation Thread Forum Replies Calculus & Beyond Homework 0 Engineering, Comp Sci, & Technology Homework 9 Engineering, Comp Sci, & Technology Homework 1 Calculus & Beyond Homework 3 Differential Equations 13