The final image in an astronomical telescope is:

An astronomical telescope, commonly taught in class 12 physics, is an optical device used to observe distant celestial objects by magnifying their images. To understand the type of final image formed in an astronomical telescope, it is essential to consider its structure and functioning.

An astronomical telescope class 12 consists of two major convex lenses:

• Objective Lens: This is the larger lens with a longer focal length. It gathers light from distant objects and forms an intermediate real, inverted image.
• Eyepiece Lens: This is the smaller lens with a shorter focal length. It acts as a simple magnifier, further enlarging the intermediate image formed by the objective lens.

The final image in an astronomical telescope is formed when the intermediate image created by the objective lens is viewed through the eyepiece lens. Due to the design of the telescope and its short focal length, the final image observed through an astronomical telescope is always:

• Virtual: It cannot be projected onto a screen as it is formed behind the eyepiece.
• Inverted: The image appears upside down due to the nature of the optical system.
• Enlarged: The eyepiece magnifies the intermediate image, making it appear larger to the observer.

In the context of the astronomical telescope class 12 syllabus, it is important to note that the objective lens has a larger aperture to collect more light from faint celestial objects, ensuring a bright and clear image. The total length of the telescope is the sum of the focal lengths of the objective lens and the eyepiece lens.

The functioning of an astronomical telescope, as explained in class 12, is a vital concept in optics. The larger aperture of the objective lens ensures better light-gathering capacity, while the eyepiece provides magnification. Hence, the final image formed by an astronomical telescope is virtual, inverted, and enlarged, allowing astronomers to observe far-off celestial bodies with clarity.

Correct Answer: Option B