A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since

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A lens of large focal length and large aperture is best suited as an objective of an astronomical telescope since

(1) A large aperture contributes to the quality and visibility of the images.

(2) A large area of the objective ensures better light-gathering power.

(3) A large aperture provides a better resolution.

(4) All of the above

Solution: Answer (4)

The light gathering power of a telescope increases as the objective lens aperture increases. The diameter of the objective also affects the resolving power, or the capacity to distinguish between two objects. As a result, a large diameter goal is favoured. Also, larger diameters allow for the observation of fainter objects. As a result, it also helps to improve image quality and visibility. As a result, all of the selections are correct.

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