Question

Write two properties of a fuse wire.

Hint:

Fuse wires are commonly made of an alloy of lead and tin to achieve the desired low melting point.

Answer 1

Step 1: Understanding the Concept:
A fuse is a safety device designed to melt and break the circuit if the current exceeds a safe limit.

Step 2: Detailed Explanation:
To function correctly, the fuse wire must heat up faster than the rest of the circuit wiring.
1. It must have relatively high resistance so that a significant amount of heat is generated in it according to Joule's law (\(H = I^2Rt\)).
2. It must have a low melting point so that it melts quickly and breaks the circuit before the high current can damage appliances or cause a fire.

Step 3: Final Answer:
The two key properties are high resistance and low melting point.