What safety device in an electrical plug or consumer unit contains a thin metal wire designed to melt when current exceeds safe limits?
Answer and explanation
Correct answer: D. A fuse
- Step 1: A fuse is a critical safety component containing a wire of low melting point rated for a specific current. Step 2. Excessive electric current heats the wire by Joule heating until it melts, breaking the circuit before wiring can ignite. Answer: A fuse. Why not the others: A switch mechanically opens/closes circuits; a resistor limits current; a capacitor stores electrical charge.
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