Question

An object is placed at the focus of concave lens of focal length 30 cm.Where will the image form?​

Answer 1

At 15 cm.

This is because when the object is kept on the focus point of the concave lens, the image will be formed at a distance equal to half its focal length.

Here, the focal length of the lens is 30 cm,

So, 1/2 of 30 will be 15.

Hence, the image will be formed at a distance of 15 cm in front of the lens.

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