Rohit placed a pencil perpendicular to principal axis in front of a converging
mirror of focal length 30 cm. The image formed is twice the size of the pencil.
Calculate the distance of the object from the mirror.

Light from two different sources are incident upon the same side of a polarizing filter. light from one source is polarized with total intensity ip, while light from the other source is unpolarized with total intensity iu. as you rotate the polarizing filter through 360 degrees, the intensity of the transmitted light on the other side varies by a factor of 9. what is the relative intensity of the initial polarized source to the unpolarized source, or ip/iu?