A concave lens is placed in the path of convergent rays. The rays are focussed on the axis 15 cm behind the lens. Where would these rays have been focussed in the absence of the lens ? Focal length of the lens is 30 cm.

A concave lens is placed in the path of convergent rays. The rays are

1.	A concave lens is placed in the path of convergent rays. The rays are focussed on the axis 15 cm behind the lens. Where would these rays have been focussed in the absence of the lens ? Focal length of the lens is 30 cm.
Answer» Correct Answer - At a distance of 10 cm behind the lens

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A concave lens is placed in the path of convergent rays. The rays are focussed on the axis 15 cm behind the lens. Where would these rays have been focussed in the absence of the lens ? Focal length of the lens is 30 cm.

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