With the help of a diagram, explain why the image of an object viewed through a concave lens appears smaller and closer than the object.
For an object placed anywhere in front of a concave lens, the image so produced is always virtual, erect, and diminished in size.
As shown in the diagram given below, the image of an object viewed through a concave lens appears smaller and closer than the object.
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Explanation
Diverging Lens or Concave Lens $-$ It is a lens that possesses at least one surface that curves inwards in the middle. In other words, it is thin across the middle and thick at the upper and lower edges, because of which the light that enters the lens, gets spread out, or diverges, which results in forming a smaller image. Due to this effect, it is also called a negative lens or a diverging lens.
The image formed by a concave lens is always virtual, erect, and diminished.
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