If a 1 MΩ resistor, 0.47 MΩ resistor and 0.5 MΩ resistor are connected in parallel across an 18V source, what is the total current if the 1 MΩ resistor opens?
A)74.3 µA
B)92.3 µA
C)74.3 mA
D)92.3 mA

Question

Quizplus · Accepted Answer

When the 1 MΩ resistor opens, only the 0.47 MΩ and 0.5 MΩ resistors are in parallel. The equivalent resistance is calculated as 1/(1/0.47 + 1/0.5) MΩ = 0.243 MΩ. The total current is then I = V/R = 18V / 0.243 MΩ = 74.3 µA.

If a 1 MΩ Resistor, 0