What is the answer for this question & explain me why---**Question:** 3. Case: Magnetic Art Project If Zoe accidentally drops her box of iron nails and they mix with some aluminum scraps, how could she easily separate them? 👜 **Options:** A. By hand B. Using water C. Using a magnet D. Using a fan

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Let's examine this magnetic separation problem. Zoe has accidentally mixed iron nails with aluminum scraps. We need to find the best method to separate these two different materials. The key is understanding the magnetic properties of iron versus aluminum. To understand why a magnet works for separation, we need to examine the magnetic properties of these materials. Iron is a ferromagnetic material with unpaired electrons that create magnetic domains, making it strongly attracted to magnets. Aluminum, however, is non-magnetic with paired electrons that cancel out magnetic effects, so it's not attracted to magnets. Now let's see magnetic separation in action. When we bring a magnet close to the mixture, the magnetic field lines extend outward. The iron nails are strongly attracted and move toward the magnet, while the aluminum scraps remain completely unaffected. This allows us to easily lift the iron nails with the magnet, leaving the aluminum behind. Let's examine why the other options don't work. Separating by hand would be time-consuming and potentially dangerous with sharp edges. Using water won't help because both iron and aluminum are denser than water and will sink. A fan is ineffective because both materials are too heavy to be moved by air. Only the magnet exploits the fundamental difference in magnetic properties between iron and aluminum. Let's analyze this practical problem step by step. Zoe has accidentally mixed iron nails with aluminum scraps. We need to find the most efficient way to separate these two different materials. Let's examine each option carefully. To solve this problem, we need to understand the magnetic properties of these materials. Iron is ferromagnetic, meaning it's strongly attracted to magnets due to its atomic structure and unpaired electrons. Aluminum, however, is non-magnetic and shows no attraction to magnets. This fundamental difference in magnetic properties is what makes separation possible. Let's analyze each option systematically. Option A, separating by hand, would be time-consuming and potentially dangerous. Option B, using water, won't work because both iron and aluminum are denser than water and would sink. Option D, using a fan, might move lighter pieces but won't separate based on material type. Option C, using a magnet, is the clear winner because it exploits the fundamental difference in magnetic properties. Now let's see magnetic separation in action. When we bring a magnet close to the mixture, the iron nails are strongly attracted to the magnet due to their ferromagnetic properties. The magnetic field lines show how the magnetic force extends outward from the magnet. The aluminum scraps, being non-magnetic, remain unaffected and stay in place. This creates a clean, efficient separation. In conclusion, the correct answer is C - using a magnet. This solution works because iron is ferromagnetic and strongly attracted to magnets, while aluminum is non-magnetic and unaffected. This principle is widely used in recycling centers, mining operations, and scrap metal processing. Understanding material properties allows us to find elegant solutions to practical problems.