Question

Two fuse wires of the same length are rated 5 A and 15 A. Which of the two fuse wires is thicker and why?

Answer 1

1. If we observe two wires having the same length and one of them draws more current, then we understood that the wire drawing more current is having less resistance.
2. Resistance is the property that is directly proportional to length but inversely proportional to the area of cross-section.
3. So, more current means less resistance, which means more thickness of the wire.
4. Thus, if the current drawn in the second wire is high as compared to the first, it means the area of the cross-section of the wire having $15A$is thicker than the wire having a current of $5A.$