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Why is an astronomical telescope made with a large aperture?

1. To minimize spherical aberration
2. To obtain greater resolving power
3. To widen the field covered by the instrument
4. To reduce chromatic dispersion

Correct answer: To obtain greater resolving power

Solution

A larger aperture allows more light to enter the telescope, which enhances its ability to distinguish fine details and separate closely spaced objects, thereby increasing its resolving power.

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