Physics
State the condition for each of the following :
(a) a lens has both its focal lengths equal.
(b) a ray passes undeviated through the lens.
Related Questions
Define the term focal length of a lens.
What do you mean by focal plane of a lens?
Complete the following sentences —
(a) If half part of a convex lens is covered, the focal length …………… change, but the intensity of image …………….
(b) The focal length of a thin convex lens is …………… than that of a thick convex lens.
(c) A tumbler filled with water behaves as a …………… lens.
Name the two kinds of lens? Draw diagrams to illustrate them.