A paramagnetic material is placed in a magnetic field. Consider the following statements : (A) If the magnetic field is increased, the magnetization is increased. (B) If the temperature is increased, the increased the magnetization is increased.

Options

A. Both A and B are ture
B. A is true but B is false
C. B is true but A is false
D. Both A and B are false.

Answer

To analyze the statements regarding a paramagnetic material placed in a magnetic field, we will evaluate each statement step by step.

### Step 1: Understanding Magnetization in Paramagnetic Materials
Magnetization (I) in a paramagnetic material is defined as the magnetic moment per unit volume. It is influenced by the external magnetic field (H) and temperature (T).

### Step 2: Evaluating Statement A
**Statement A:** "If the magnetic field is increased, the magnetization is increased."

- According to the relationship between magnetization (I) and magnetic field (H), we can express magnetization as:
\[ I = \chi \cdot H \]
where \(\chi\) is the magnetic susceptibility of the material.

- In paramagnetic materials, the magnetic susceptibility (\(\chi\)) is positive and typically increases with the magnetic field. Therefore, if we increase the magnetic field (H), the magnetization (I) will also increase.

**Conclusion for Statement A:** This statement is **true**.

### Step 3: Evaluating Statement B
**Statement B:** "If the temperature is increased, the magnetization is increased."

- The magnetization in paramagnetic materials is inversely related to temperature. This relationship can be expressed as:
\[ I \propto \frac{1}{T} \]

- As the temperature (T) increases, the thermal agitation of the magnetic dipoles also increases, which tends to randomize their alignment with the magnetic field, resulting in a decrease in magnetization (I).

**Conclusion for Statement B:** This statement is **false**.

### Final Conclusion
- Statement A is **true**: Increasing the magnetic field increases magnetization.
- Statement B is **false**: Increasing the temperature decreases magnetization.