Question

The equivalent to the given circuit is

I got this question by my school principal while I was bunking the class.

I'd like to ask this question from Network Theroms topic in chapter EDC Overview of Electronic Devices & Circuits

Answer 1

In the context of Network Theorems, the question "The equivalent to the given circuit is" typically asks you to find the simplified equivalent circuit using one of the network theorems, such as Thevenin's Theorem, Norton's Theorem, Superposition Theorem, Maximum Power Transfer Theorem, or Millman's Theorem.

Here's how to approach this kind of problem:

1. Thevenin's Theorem:

   • Find the open-circuit voltage across the load (this is the Thevenin voltage VthV_{th}Vth​).
   • Find the equivalent resistance seen from the load (with all independent voltage and current sources replaced by their internal resistances). This is the Thevenin resistance RthR_{th}Rth​.
   • The equivalent circuit will be a voltage source VthV_{th}Vth​ in series with a resistance RthR_{th}Rth​.

2. Norton's Theorem:

   • Find the short-circuit current across the load (this is the Norton current INI_NIN​).
   • Find the equivalent resistance seen from the load (this is the same as the Thevenin resistance RthR_{th}Rth​).
   • The equivalent circuit will be a current source INI_NIN​ in parallel with a resistance RthR_{th}Rth​.

3. Superposition Theorem:

   • If there are multiple sources, solve for the response (voltage or current) from each source independently, and then sum the effects.

4. Maximum Power Transfer Theorem:

   • If the question asks for the condition for maximum power transfer, this occurs when the load resistance equals the Thevenin (or Norton) resistance seen by the load.

5. Millman's Theorem:

   • This is useful when you have multiple sources with a common node. The equivalent voltage at that node is the weighted average of the sources.

Example:

Given a circuit with resistors and sources, use the relevant theorem to find the simplified equivalent circuit, whether it’s Thevenin or Norton equivalent.

Would you like help with a specific type of network or theorem for this?