How do a short circuit and an overload differ in a circuit?

• A. A short circuit causes an overload without changing resistance; an overload creates near-zero resistance.
• B. A short circuit causes a near-zero resistance path with excessive current; an overload draws more current than the circuit rating under normal resistance.
• C. A short circuit reduces voltage; an overload increases voltage.
• D. A short circuit and an overload are the same condition.

Answer: (B)

Key idea: understand how resistance and current behave in a circuit. A short circuit creates a path of very low resistance, so the current surges high because the source voltage pushes as much current as the near-zero resistance allows. This sudden, excessive current is what triggers protective devices and can cause damage or overheating. An overload happens when the circuit carries more current than its rating but the resistance remains as designed for the load; the current is simply higher than intended, leading to heating over time rather than an immediate surge. So the best description is that a short circuit creates a near-zero resistance path with excessive current, while an overload draws more current than the circuit rating under normal resistance. The other statements misstate how resistance or voltage behaves in these conditions.