In this material analogy, “Steel is to Rails as Alnico is to ______”. Choose the object that is commonly made from the alloy Alnico in the same way rails are made from steel.

Introduction / Context:
This analogy is based on materials and their typical uses. In the pair “Steel : Rails”, steel is the material and rails are the common product made from it, especially in railway tracks. The question then asks for a similar relationship with Alnico, which is a special alloy. You must know which objects are usually made from Alnico. This checks general science knowledge and the ability to recognise material–product relationships.

Given Data / Assumptions:

• Steel is a strong alloy of iron and carbon widely used in construction and rail tracks. • Rails are the long steel bars on which train wheels run. • Alnico is an alloy made mainly from aluminium, nickel, and cobalt, with some iron and other elements. • Options: magnets, aircraft, machinery, silver ware. • We assume basic knowledge from science textbooks about common alloys and their uses.

Concept / Approach:
Steel is chosen for rails because of its strength and durability. The relationship in the first pair is “material : product usually made from that material”. We must recall where Alnico is used. Alnico is famous for its strong permanent magnetic properties. Many permanent magnets, especially in older equipment and loudspeakers, are made from Alnico. Aircraft, general machinery, and silverware are made from other metals and alloys, not specifically from Alnico. Thus, magnets are to Alnico as rails are to steel.

Step-by-Step Solution:
Step 1: Understand the first pair. Rails are made from steel because it is strong, tough, and can bear heavy loads. So the pattern is “alloy or metal : item manufactured using that alloy or metal”. Step 2: Recall the properties of Alnico. It is known as a strong permanent magnet alloy. When it is magnetised, it retains magnetism for a long time. Step 3: Evaluate each option with this in mind. Magnets: Many permanent magnets, especially in instruments and loudspeakers, are made out of Alnico alloy. Aircraft: Modern aircraft parts are mainly made from aluminium alloys, titanium, or composite materials, not from Alnico, which is not suited for structural parts. Machinery: This is a very general term; while some parts may use magnets, machinery as a whole is not made from Alnico. Silver ware: These are items made from silver or stainless steel, not from Alnico. Step 4: Only magnets stand in the same clear “material used for” relationship with Alnico that rails do with steel.

Verification / Alternative check:
We can restate the analogy: “Rails are made of steel; magnets are made of Alnico”. This is a factual statement used in many basic science references. Attempting any other pairing gives poor factual accuracy. For example, “Aircraft are made of Alnico” is incorrect and does not represent common practice. This confirms that magnets is the only scientifically valid product to pair with Alnico in this context.

Why Other Options Are Wrong:
• Aircraft: Primarily use light and strong alloys such as aluminium alloys and titanium, not magnetic alloys like Alnico. • Machinery: Too broad and undefined. Many machines use magnets, but the entire category is not a direct product of Alnico. • Silver ware: Mostly made from silver or stainless steel, unrelated to Alnico.

Common Pitfalls:
Some students misread Alnico as a brand or think of it as a general metal. Remember that Alnico is an alloy specially designed for strong permanent magnets. Recognising this and focusing on specific, fact based material uses helps in solving many such science based analogies. A quick review of common alloys and their applications is very useful for aptitude exams.

Final Answer:
The product that completes the analogy is Magnets.