Question

The value of the focal length of the lens is equal to the value of the image distance when the rays are​

Answer 1

Answer:

parallel to each other

Answer 2

Answer:

The focal length is equal to the image distance when the object is very, very distant (e.g. a star). A positive focal length lens (a converging lens) forms a real image of the star at a distance from the lens equal to its focal length.

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