Fault effect — in a parallel resistive network, opening (going open-circuit) one branch resistor will cause the total equivalent resistance seen by the source to _____ .

Introduction / Context:Understanding how faults affect equivalent resistance helps with diagnostics. In parallel networks, each branch adds conductance (1/R). Removing a branch by opening it reduces total conductance.

Given Data / Assumptions:

• Purely resistive DC network.
• One branch goes open (infinite resistance).
• All other branches remain unchanged.

Concept / Approach:Total conductance G_total = Σ(1/Ri). If one branch opens, its 1/R term becomes 0, so G_total decreases, meaning R_total = 1/G_total increases. Source current drops accordingly for a fixed source voltage.

Step-by-Step Solution:

Verification / Alternative check:Try numbers: parallel of 6 kΩ and 12 kΩ is 4 kΩ; opening the 12 kΩ branch leaves 6 kΩ, which is larger than 4 kΩ.

Why Other Options Are Wrong:

Common Pitfalls:Thinking of voltage division (series behavior) instead of conductance addition in parallel.

Final Answer:Increase