For the loop shown in the figure, which expression matches Kirchhoff's Voltage Law as written in the notes? 
A$V_1+V_2+V_3+V_4+V_5+V_6+V_7-V_s=0$
B$V_s+V_1+V_2+V_3+V_4+V_5+V_6+V_7=0$
C$V_s-(V_1+V_2+V_3+V_4+V_5+V_6+V_7)=0$
D$V_1+V_2+V_3+V_4-V_5-V_6-V_7=0$
Answer & Solution
Correct answer: A. $V_1+V_2+V_3+V_4+V_5+V_6+V_7-V_s=0$
The figure and note indicate that the source is taken with opposite sign to the voltage drops across the other elements. Hence the loop equation is $V_1+V_2+V_3+V_4+V_5+V_6+V_7-V_s=0$. Option C is algebraically equivalent, but the question asks for the form written in the notes.
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