일반물리학 2 — Circuits: Problem 14

14 The resistances in Fig. 27-27a and b are all 4.0 $\Omega$, and the batteries are ideal 12 V batteries. (a) When switch S in Fig. 27-27a is closed, what is the change in the electric potential $V_1$ across resistor 1, or does $V_1$ remain the same? (b) When switch S in Fig. 27-27b is closed, what is the change in $V_1$ across resistor 1, or does $V_1$ remain the same?