Faults in series circuits: Does a short circuit in a series path prevent current flow? Analyze the effect of an unintended short (near-zero resistance connection) placed in series with other elements powered by a DC source.

Introduction / Context:Mistaking the effect of a short in a series circuit is common. This question checks whether learners understand that a short generally lowers resistance and increases current, rather than preventing it.

Given Data / Assumptions:

• DC steady-state operation.
• An “ideal short” means resistance approaching zero.
• Components are in series unless a fault bridges across something.

Concept / Approach:

In series networks, total resistance RT is the sum of element resistances. Introducing a short as a replacement for a series element reduces that element’s resistance to approximately zero, thus lowering RT and increasing current. A condition that truly prevents current is an open circuit (infinite resistance), not a short (near-zero resistance).

Step-by-Step Solution:

Verification / Alternative check:

Compare with an open: replacing an element by an open makes RT → ∞ and I → 0, which truly prevents current. Therefore, “prevents current” describes an open, not a short, in a series path.

Why Other Options Are Wrong:

• “True” confuses short with open.
• Polarity reversal does not convert a short to an open; current direction changes sign but still flows.
• “Only when the short is across the source terminals” actually creates extremely large current, still not zero (though it is a dangerous fault).
• AC/reactive specifics do not change the fundamental effect of a short’s very low impedance.

Common Pitfalls:

Assuming “fault” automatically means no current. Shorts can cause excessive current and damage rather than interruption.

Final Answer:

False