Which of these materials requires the least value of magnetic field strength to magnetize it ?

Options

A. Nickel
B. Silver
C. Tungsten
D. Sodium Chloride

Answer

To determine which of the materials requires the least value of magnetic field strength to magnetize, we need to analyze the magnetic properties of each option provided.

### Step-by-Step Solution:

1. **Identify the Materials**: The materials given in the options are:
- A) Nickel
- B) Silver
- C) Tungsten
- D) Sodium Chloride

2. **Classify the Materials**: We need to classify these materials based on their magnetic properties:
- **Nickel**: This is a ferromagnetic material, which means it can be easily magnetized and retains its magnetism.
- **Silver**: This is a diamagnetic material, which means it is weakly repelled by a magnetic field and does not retain magnetism.
- **Tungsten**: This is a paramagnetic material, which means it is weakly attracted by a magnetic field but does not retain magnetism.
- **Sodium Chloride**: This is also a diamagnetic material.

3. **Determine Magnetization Strength**: Among these materials, ferromagnetic materials require a lower magnetic field strength to become magnetized compared to paramagnetic and diamagnetic materials.

4. **Conclusion**: Since nickel is the only ferromagnetic material among the options, it will require the least value of magnetic field strength to magnetize.

### Final Answer:
The material that requires the least value of magnetic field strength to magnetize is **Nickel (Option A)**.

---