Engineering Can Kirchoff's laws and Ohm's law be used on circuits with diodes?

AI Thread Summary
Kirchhoff's voltage and current laws can be applied to circuits with diodes, as these laws hold true regardless of the presence of nonlinear elements. However, the principle of superposition is not applicable when analyzing circuits with diodes. Ohm's law, defined as V=IR, assumes constant resistance, which does not apply to nonlinear elements like diodes where resistance varies with voltage and current. Instead, resistance for nonlinear components can be defined using R = V/I or R = dV/dI. Understanding these principles is crucial for accurately analyzing circuits that include diodes.
SiennaB
Messages
15
Reaction score
0

Homework Statement



Can Kirchhoff's voltage and current laws, and Ohm's law, be used when analysing circuits with constant voltage and current sources, but also diodes?

I'm trying to analyse such a circuit, and I'm finding that current is flowing backwards through one of the diodes.

Homework Equations



Kirchhoff's Voltage Law: sum of voltage drops in a closed loop is zero.
Kirchhoff's Current Law: sum of currents entering a node equals sum of currents leaving a node.
Ohm's Law: V=IR

The Attempt at a Solution


 
Physics news on Phys.org
Kirchhoff's Laws that is the current law(KCL) and the Voltage law(KVL) is indeed valid everywhere, whether the circuit contains diodes, transistors or any other nonlinear element.

The thing which is not valid with the nonlinear elements in circuit is the principal of superposition.

Regarding your question on Ohm's Law, ohm's law is not basically a law. when we say V=IR, means the resistance of the element is constant. For nonlinear elements resistance in not usually important, as V is not linear to I. We still define resistance of nonlinear elements using R-= V/I or R = dV/dI.
 
  • Like
Likes 1 person
Great, thanks for your reply.
 
you are welcome!
 
Back
Top