The composition of alloy permalloy is iron and

1. Analyze the question

The question asks for the specific metal that, when combined with iron, forms the alloy known as permalloy.

2. Explain the concept

An alloy is a homogeneous mixture of two or more elements, where at least one of the elements is a metal. Alloys are created to improve the properties of the base metal, such as increasing strength, resistance to corrosion, or modifying magnetic properties.

Permalloy is a specialized alloy famous for its high magnetic permeability. This means it is very easy to magnetize and demagnetize, making it essential for use in electrical and electronic devices like transformers, magnetic shielding, and sensors.

3. Show the solution

• Composition: Permalloy is primarily composed of nickel (Ni) and iron (Fe).
• Typical Ratio: It usually contains about 80% nickel and 20% iron.
• Properties: Because of its high nickel content, it has a very low coercivity and near-zero magnetostriction, which is why it is used in high-performance magnetic applications.

Comparing this to the options provided:

• A. Copper: Combined with iron, this does not form permalloy.
• B. Nickel: This is the correct component that forms permalloy with iron.
• C. Lead: Lead is often used in solders, not in magnetic alloys like permalloy.
• D. Magnesium: Magnesium is typically used in lightweight alloys (like magnalium), not permalloy.

4. Identify the answer

The correct option is B.

5. Exam Tip

To remember this for your JAMB exam, think of the name: Perm-alloy. The "Perm" stands for Permeability (magnetic), and the "alloy" is the mixture. Since nickel is the metal most associated with high magnetic permeability in alloys, associate "Permalloy" with "Nickel."