When an object is kept in between two plane mirrors placed parallel and facing each other, we get infinite images. But actually only a few images are visible because the intensity of the image is

Options

A. Increased after each reflection
B. Decreased after each reflection
C. Always constant
D. None of these

Explanation

To solve the question about the visibility of images formed by two parallel mirrors, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Understanding the Setup**:
- We have two plane mirrors (let's call them M1 and M2) placed parallel to each other and facing each other.
- An object is placed between these mirrors.

2. **Formation of Images**:
- When light from the object reflects off the mirrors, it creates images. The first image (I1) is formed by the reflection of the object in the first mirror (M1).
- The second image (I2) is formed by the reflection of the first image (I1) in the second mirror (M2).
- This process continues, creating an infinite series of images (I3, I4, etc.) as each image acts as an object for the opposite mirror.

3. **Infinite Images**:
- Theoretically, an infinite number of images can be produced due to the continuous reflections between the two mirrors. However, in practice, we observe only a few of these images.

4. **Intensity of Images**:
- Each time light reflects off a mirror, a small portion of the light is absorbed by the mirror. This means that not all the light is reflected; some of it is lost.
- For example, if a mirror reflects 98% of the light, it absorbs 2%. This absorption leads to a decrease in the intensity of the images.

5. **Decrease in Visibility**:
- As the number of reflections increases, the intensity of the images decreases because each reflection results in some loss of light.
- Consequently, while the first image may be bright, subsequent images become progressively dimmer. Eventually, the images become so faint that they are not visible to the human eye.

6. **Conclusion**:
- Thus, while theoretically, there are infinite images formed, practically, only a few images are visible due to the gradual decrease in intensity caused by the absorption of light by the mirrors.

### Final Answer:
The intensity of the images decreases due to the absorption of light by the mirrors during each reflection, which results in only a few images being visible.

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