The position, relative size and nature of the image formed by a concave lens for an object placed at infinity are respectively

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Q: 76 (CDS-I/2014)
The position, relative size and nature of the image formed by a concave lens for an object placed at infinity are respectively

question_subject: 

Science

question_exam: 

CDS-I

stats: 

0,18,22,18,11,8,3

keywords: 

{'concave lens': [0, 1, 6, 5], 'focus': [1, 0, 0, 5], 'optical centre': [0, 0, 0, 1], 'image': [0, 1, 3, 23], 'infinity': [0, 0, 1, 7], 'object': [1, 0, 11, 43], 'position': [3, 2, 7, 11], 'relative size': [0, 0, 0, 1]}

Option 1 states that the image formed by a concave lens when an object is placed at infinity is at the focus, diminished, and virtual.

Let`s analyze each component of the option:

1. "At focus": Concave lenses converge incoming light rays, meaning they bring them closer together. When an object is placed at infinity, the light rays from the object appear parallel. These parallel light rays are refracted by the concave lens and converge at a focal point. Therefore, the image formed is at the focus.

2. "Diminished": When an image is smaller in size compared to the object, we say it is diminished. In the case of a concave lens, the image formed is smaller than the object due to the divergence of light rays after refraction. Hence, the image is diminished.

3. "Virtual": A virtual image is formed when the light rays do not actually pass through the image but appear to originate from a position behind the lens. In the case of a concave lens, the image is formed on the same side as the object, and it is virtual because the light rays do not converge to a point after refraction.

Therefore, option 1 is correct in stating that the image formed by a concave lens for