Browse Questions

# To find the focal length of a convex mirror we use indirect method because ,

$(a)\;\text{Image formed by convex mirror is always at infinity } \\(b)\;\text{Image formed by convex mirror is inverted } \\(c)\;\text{Image formed by convex mirror is always virtual } \\(d)\;\text{It focal length is very large}$

As a convex mirror always forms virtual images,its focal length cannot be found directly , so indirect method is used such as an auxillary convex lens is introduced.
Hence c is the correct answer.