The correct option is (a).
Explanation
Image formation by a plane mirror is based on the laws of reflection. The image formed is always virtual, erect, and of the same size as the object. The distance of the image behind the mirror is equal to the distance of the object in front of it.
Statement-wise Analysis:
- Statement 1 is Correct: When a candle is placed in front of a plane mirror, the image appears to be located behind the mirror. To an observer, it appears as though a similar candle is placed at that specific position behind the reflecting surface.
- Statement 2 is Incorrect: In optics, the physical entity (the candle) placed in front of the mirror is referred to as the object. The visual representation formed by the mirror is referred to as the image.
- Statement 3 is Incorrect: The image formed by a plane mirror is a virtual image. A virtual image is formed when light rays appear to diverge from a point behind the mirror but do not actually meet there. Consequently, such an image cannot be obtained on a screen. A real image, in contrast, is formed when light rays actually converge and can be projected onto a screen.
Key Takeaway:
A plane mirror always forms a virtual and erect image. The physical source is the object, while the reflection seen is the image, which appears to be behind the mirror.