Question 891 of 949
Which of the following statements correctly describes the characteristics of an image formed by a plane mirror?
- The image is always real and inverted.
- The image is virtual, upright, and the same size as the object.
- The image can be projected onto a screen.
- The image appears to be located behind the mirror at a distance greater than the actual object distance.
Correct Answer:
B
Explanation
The correct option is **B. The image is virtual, upright, and the same size as the object.**
### Detailed Explanation:
1. **Understanding Plane Mirrors:**
- A plane mirror is a flat, reflective surface that reflects light according to the law of reflection, which states that the angle of incidence is equal to the angle of reflection.
- When light rays hit a plane mirror, they reflect off the surface and appear to come from a point behind the mirror.
2. **Characteristics of the Image:**
- **Virtual Image:** The image formed by a plane mirror is virtual. This means that the light rays do not actually converge at the location of the image; instead, they appear to diverge from a point behind the mirror. You cannot project this image onto a screen because it does not exist in physical space.
- **Upright:** The image is upright, meaning it has the same orientation as the object. If you stand in front of a plane mirror, you see yourself as you are, not upside down.
- **Same Size:** The image is the same size as the object. If you are 1.7 meters tall, your image in the mirror will also appear to be 1.7 meters tall.
3. **Why Other Options Are Incorrect:**
- **Option A: The image is always real and inverted.**
- This statement is incorrect because the image formed by a plane mirror is not real; it is virtual. Real images can be projected onto a screen and are formed by converging light rays, which is not the case with plane mirrors.
- Additionally, the image is not inverted; it maintains the same orientation as the object.
- **Option C: The image can be projected onto a screen.**
- This option is incorrect because, as mentioned earlier, the image formed by a plane mirror is virtual. Virtual images cannot be projected onto a screen since they do not exist at a physical location where light converges.
- **Option D: The image appears to be located behind the mirror at a distance greater than the actual object distance.**
- This statement is misleading. While it is true that the image appears to be behind the mirror, it is not at a distance greater than the object distance. In fact, the distance of the image behind the mirror is equal to the distance of the object in front of the mirror. For example, if an object is 2 meters in front of the mirror, the virtual image will appear to be 2 meters behind the mirror.
### Summary of Key Points:
- The image formed by a plane mirror is **virtual**, **upright**, and **the same size** as the object.
- It cannot be projected onto a screen because it does not exist in physical space.
- The image appears to be located behind the mirror at a distance equal to the object distance, not greater.
### Revision Summary:
- Plane mirrors create **virtual images** that cannot be projected.
- The images are **upright** and **identical in size** to the object.
- The distance of the image behind the mirror equals the distance of the object in front of it.