Eduprobe
Question:
Study the given ray diagrams and select the correct statement from the following: Device X is a concave lens and device Y is a convex mirror, whose focal lengths are 20cm and 25cm respectively. Device X is a concave mirror and device Y is a convex lens, whose focal lengths are 20cm and 25cm respectively. Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 20cm and 25cm respectively. Device X is a concave lens and device Y is a concave mirror, whose focal lengths are 20cm and 25cm respectively.
Device X is a concave lens and device Y is a convex mirror, whose focal lengths are 20cm and 25cm respectively.
Device X is a concave mirror and device Y is a convex lens, whose focal lengths are 20cm and 25cm respectively.
Device X is a convex lens and device Y is a concave mirror, whose focal lengths are 20cm and 25cm respectively.
Device X is a concave lens and device Y is a concave mirror, whose focal lengths are 20cm and 25cm respectively.
Solution:
In the first case, The ray of light is converging, when passing from lens X, so it is a convex lens. In the second case, the ray of light is diverging, when getting reflected from the mirror Y, so it is a concave mirror.