Which of the following statement (s) is/are true?

Options

A. In vaccum the speed of red colour is more than that of violet colour
B. An object in front of a mirror is moved towards the pole of a spherical mirror from infinity, it is found that image also moves towards the pole. The mirror must be convex
C. There exist two angles of incidence in a prism for which angles of deviation are same except minimum deviation
D. A ray travels from a rarer medium to denser medium. There exist three angles of incidence for which the deviation is same

Explanation

To determine which of the statements are true, we will analyze each statement one by one.

### Step-by-Step Solution:

1. **Statement 1**: "In vacuum, the speed of red color is more than that of violet color."
- In a vacuum, all electromagnetic waves travel at the same speed, which is the speed of light (approximately \(3 \times 10^8\) m/s). This includes all colors of light, such as red and violet. Therefore, this statement is **false**.

2. **Statement 2**: "An object in front of a mirror is moved towards the pole of a spherical mirror from infinity. It is found that the image also moves towards the pole; the mirror must be convex."
- For a convex mirror, when an object is moved from infinity towards the mirror, the image formed by the mirror also moves towards the pole. The image is virtual, erect, and diminished. Thus, this statement is **true**.

3. **Statement 3**: "There exist two angles of incidence in a prism for which angles of deviation are the same except the minimum deviation."
- The graph of angle of deviation versus angle of incidence for a prism shows that for certain angles of incidence, the angle of deviation can be the same. This means that there can be two different angles of incidence that yield the same angle of deviation, except for the case of minimum deviation. Hence, this statement is **true**.

4. **Statement 4**: "An array travels from a regular medium to a denser medium. There exist three angles of incidence for each deviation."
- This statement is incorrect. For a plane interface between two media, there is only one angle of incidence that corresponds to a specific angle of deviation. The phenomenon described is not applicable to a prism, and thus this statement is **false**.

### Conclusion:
The true statements are:
- **Statement 2**: True
- **Statement 3**: True

### Final Answer:
The correct options are **Statement 2 and Statement 3**.

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