In case of displacement method of lenses, the product of magnification in both cases is

Options

A. 1
B. 2
C. Zero
D. Infinite

Answer

To solve the question regarding the product of magnification in the displacement method of lenses, we can follow these steps:

### Step-by-Step Solution:

1. **Understanding Magnification**:
Magnification (M) is defined as the ratio of the image distance (v) to the object distance (u). For two lenses, we can denote their magnifications as:
- \( M_1 = \frac{v_1}{u_1} \) for the first lens
- \( M_2 = \frac{v_2}{u_2} \) for the second lens

2. **Calculating the Product of Magnifications**:
To find the product of the magnifications from both lenses, we multiply \( M_1 \) and \( M_2 \):
\[ M_1 \times M_2 = \left(\frac{v_1}{u_1}\right) \times \left(\frac{v_2}{u_2}\right) \]

3. **Using the Displacement Method**:
In the displacement method, the object distance and image distance are related in such a way that the product of the magnifications simplifies. Specifically, if the two lenses are used in succession, the overall magnification can be shown to equal 1 under certain conditions (like when the object and image are at the same distances for both lenses).

4. **Conclusion**:
Therefore, the product of the magnifications \( M_1 \times M_2 \) equals 1:
\[ M_1 \times M_2 = 1 \]

### Final Answer:
The product of magnification in both cases is **1** (Option 1).

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