Image formed by a mirror is always straight whatever will be the distance, then mirror is:

Options

A. only plane
B. only concave
C. only convex
D. either plane or convex

Answer

To solve the question, "Image formed by a mirror is always straight whatever will be the distance, then mirror is:", we will analyze the properties of different types of mirrors.

### Step-by-Step Solution:

1. **Understanding the Types of Mirrors**:
- There are three main types of mirrors: plane mirrors, concave mirrors, and convex mirrors.
- Each type of mirror has different properties regarding the images they form.

2. **Analyzing Plane Mirrors**:
- A plane mirror always forms a virtual image that is upright (straight) and of the same size as the object, regardless of the distance of the object from the mirror.
- Therefore, if the image is always straight, a plane mirror could be a possible answer.

3. **Analyzing Concave Mirrors**:
- Concave mirrors can form both real and virtual images.
- A real image formed by a concave mirror is inverted (not straight), while a virtual image is upright but only occurs when the object is placed between the focal point and the mirror.
- Since the question states that the image is always straight, a concave mirror cannot be the answer.

4. **Analyzing Convex Mirrors**:
- Convex mirrors always form virtual images that are upright (straight) and smaller than the object, regardless of the distance of the object from the mirror.
- Thus, a convex mirror also satisfies the condition of forming a straight image.

5. **Conclusion**:
- Since both plane and convex mirrors can produce straight images, the correct answer to the question is that the mirror can be either a plane mirror or a convex mirror.
- Therefore, the correct option is "either plain or convex".

### Final Answer:
The mirror is either a plane mirror or a convex mirror.

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