Which statement correctly describes Norton’s theorem in relation to Thevenin’s theorem?

Which statement correctly describes Norton’s theorem in relation to Thevenin’s theorem?

• A. The Norton model is a voltage source in series with Rn.
• B. The Norton model is a current source In in parallel with Rn, where In = Vth / Rth and Rn = Rth.
• C. The Norton model is a voltage source Vth in parallel with Rth.
• D. The Norton model has no relation to Thevenin.

Answer: (B)

The main idea here is that Norton’s theorem provides a current-source version that is equivalent to Thevenin’s voltage-source version for any load connected to the same two terminals. In Norton form, you have a current source in parallel with a resistor. The current value is In = Vth / Rth and the parallel resistor is Rn = Rth. This comes from the source transformation: a voltage source Vth in series with Rth can be converted into a current source of value Vth / Rth in parallel with the same resistance, yielding the same terminal behavior for any connected load. That’s why the described statement is the correct way to express Norton’s model. The other options mix up series vs parallel arrangements or ignore the link to Thevenin, which is not accurate.

The main idea here is that Norton’s theorem provides a current-source version that is equivalent to Thevenin’s voltage-source version for any load connected to the same two terminals. In Norton form, you have a current source in parallel with a resistor. The current value is In = Vth / Rth and the parallel resistor is Rn = Rth. This comes from the source transformation: a voltage source Vth in series with Rth can be converted into a current source of value Vth / Rth in parallel with the same resistance, yielding the same terminal behavior for any connected load. That’s why the described statement is the correct way to express Norton’s model. The other options mix up series vs parallel arrangements or ignore the link to Thevenin, which is not accurate.