A small device pulls iron nails from a distance. Which type of force is involved in this process?

Options

A. Electrostatic force
B. Frictional force
C. Magnetic force
D. Gravitational force

Answer

**Step-by-Step Solution:**

1. **Identify the Object and Its Material**: The question mentions a small device that pulls iron nails. Since iron nails are made of iron, we recognize that iron is a metal.

2. **Determine the Nature of Interaction**: The device pulls the nails from a distance, which indicates that there is no physical contact between the device and the nails when the pulling occurs.

3. **Classify the Type of Force**: Since the force acts at a distance without direct contact, we categorize this as a non-contact force.

4. **Identify the Specific Non-Contact Force**: Among non-contact forces, we know that magnetic force is a type of force that can attract certain metals, including iron.

5. **Conclude the Type of Force Involved**: Therefore, the force involved in pulling the iron nails from a distance by the small device is identified as magnetic force.

6. **Identify the Device**: The small device that pulls the iron nails is a magnet, which utilizes magnetic force to attract the nails.

**Final Answer**: The type of force involved in this process is magnetic force.

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