If the image formed by a lens for all positions of the object placed in front of it is always virtual

CBSE Class 10 CBSE Class 10 Science
, ,
1

If the image formed by a lens for all positions of the object placed in front of it is always virtual, erect and diminished, state the types of lens. Draw a ray diagram in support of your answer, if the numerical value of focal length of such a lens is 20 cm. Find its power in new cartesian of convention.

2

A concave lens will always give a virtual, erect and diminished image, irrespective of the position of the object.

image
image.png716×174 10.2 KB

Given, focal length f = -20 cm = -0.2 m (negative for convex lens)
image