In the following hexagons made up of two different material P and Q, current enters and leave from points X and Y respectively.In which case the magnetic field its center is not zero
The correct answer is option (A):
Two identical concave mirrors each of focal length $ f $ are facing each other as shown. A glass slab of thickness $ t $ and refractive index $ n_0 $ is placed equidistant from both mirrors on the principal axis. A monochromatic point source $ S $ is placed at the center of the slab. For the image to be formed on $ S $ itself, which of the following distances between the two mirrors is/are correct: