### Correct Option: B. Real and inverted ### Detailed Explanation: When a parallel beam of light strikes a concave mirror, the behavior of the light rays can be analyzed using the principles of reflection and the properties of concave mirrors. 1. **Understanding Concave Mirrors**: - A concave mirror is a spherical mirror that curves inward, resembling a portion of the interior of a sphere. - The focal point (F) of a concave mirror is the point where parallel rays of light converge after reflecting off the mirror. The distance from the mirror's surface to the focal point is known as the focal length (f). 2. **Behavior of Parallel Light Rays**: - When parallel rays of light (like those from a distant object) strike a concave mirror, they reflect off the mirror's surface. - According to the law of reflection, the angle of incidence equals the angle of reflection. For parallel rays, this means that they will converge at the focal point after reflection. 3. **Image Formation**: - The image formed by a concave mirror can be determined using the mirror formula and ray diagrams. - In this case, since the light rays are parallel and converge at the focal point, the image formed at this point is real. A real image is one that can be projected onto a screen, as it is formed by the actual convergence of light rays. 4. **Inversion of the Image**: - The nature of the image (upright or inverted) depends on the position of the object relative to the mirror. For a concave mirror, when the object is at infinity (which is effectively the case for parallel rays), the image formed at the focal point is inverted. - This means that if you were to place a screen at the focal point, you would see an image that is upside down compared to the original object. ### Why Other Options Are Incorrect: - **Option A: Virtual and upright**: - A virtual image is formed when the light rays do not actually converge but appear to diverge from a point behind the mirror. This occurs when the object is placed between the focal point and the mirror. Since we are discussing parallel rays converging at the focal point, this option is incorrect. - **Option C: Virtual and inverted**: - As mentioned, a virtual image cannot be inverted because it is not formed by the actual convergence of light rays. This option is contradictory and therefore incorrect. - **Option D: Real and upright**: - A real image formed by a concave mirror is always inverted when the object is at a distance greater than the focal length. Since the image at the focal point is real, it cannot be upright. Thus, this option is also incorrect. ### Summary of Key Points: - A concave mirror reflects parallel rays of light to converge at the focal point. - The image formed at the focal point is real because the light rays actually meet there. - The image is inverted due to the nature of reflection in concave mirrors. - The correct answer is B: Real and inverted. This understanding of concave mirrors and image formation is crucial for mastering optics in physics, especially in the context of mirrors and lenses.