For example, when a convex lens focusses light
to form a real image, although the ray going through the centre traverses
a shorter path, but because of the slower speed in glass, the time taken
is the same as for rays travelling near the edge of the lens Rationalised 2023-24
Physics
262
10 4  COHERENT AND INCOHERENT
ADDITION OF WAVES
In this section we will discuss the
interference pattern produced by the
superposition of two waves You may recall
that we had discussed the superposition
principle in Chapter 14 of your Class XI
textbook