In the context of electric charge $Q$ and circuit protection, what is the term for the maximum short-circuit current $I_{\mathrm{sc}}$ that a circuit breaker or fuse can safely interrupt?

• A. Thermal limit
• B. Interrupting rating
• C. Rated voltage
• D. Continuous current rating

Answer: (B)

Verified step by step guidance

1. Understand that the problem is asking for the specific term used to describe the maximum short-circuit current that a protective device like a circuit breaker or fuse can safely interrupt without damage.
2. Recall that circuit protection devices have various ratings, including continuous current rating (the maximum current they can carry continuously), rated voltage (the maximum voltage they can handle), and interrupting rating (the maximum fault current they can safely interrupt).
3. Recognize that the 'thermal limit' generally refers to temperature constraints rather than current interruption capability.
4. Identify that the term describing the maximum short-circuit current a device can safely interrupt is called the 'interrupting rating' or 'breaking capacity'.
5. Conclude that the correct term for the maximum short-circuit current a circuit breaker or fuse can safely interrupt is the 'interrupting rating'.