1. Let's state the problem: We want to find out if dividing the open circuit voltage $V_{th}$ by the dead circuit resistance $R_{th}$ or $R_n$ gives the short circuit current $I_{sc}$. 2. Thevenin's theorem states that any linear electrical network with voltage and current sources and resistances can be replaced at terminals A-B by an equivalent voltage source $V_{th}$ in series with a resistance $R_{th}$. 3. The open circuit voltage $V_{th}$ is the voltage across the terminals when no load is connected (open circuit). 4. The short circuit current $I_{sc}$ is the current that flows when the terminals are shorted (zero resistance load). 5. According to Ohm's law, current $I$ is voltage $V$ divided by resistance $R$, so for the Thevenin equivalent circuit: $$I_{sc} = \frac{V_{th}}{R_{th}}$$ 6. This means dividing the open circuit voltage $V_{th}$ by the Thevenin resistance $R_{th}$ indeed gives the short circuit current $I_{sc}$. 7. Note: $R_n$ is not a standard notation here; the correct resistance to use is the Thevenin resistance $R_{th}$. Final answer: Yes, $I_{sc} = \frac{V_{th}}{R_{th}}$ gives the short circuit current.