What will be the effect on the intensity of the image if the diameter of the objective is doubled in a telescope ?

Explanation

To determine the effect on the intensity of the image when the diameter of the objective lens (aperture) of a telescope is doubled, we can follow these steps:

### Step 1: Understand the relationship between intensity and aperture
The intensity of the image formed by a telescope is directly proportional to the area of the aperture of the objective lens. The area \( A \) of a circular aperture is given by the formula:
\[ A = \pi \left( \frac{d}{2} \right)^2 = \frac{\pi d^2}{4} \]
where \( d \) is the diameter of the aperture.
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