Figure EP 10.19 shows a two slit arrangement with a source which emits unpolarised light. P is a polariser with axis whose direction is not given. If `I_0` is the intenstiy of the principal maxima when no polariser is present, calculate in the present case, the intensity of the principal maxima as well as of the first minima.

Light from an ordianry source(say a sodium lamp) is passed through a polaroid sheet P_1 .The transmitted light is then made to pass through a second polaroid sheet P_2 ,which can be rotated so that the angle (theta) betwen the two polaroid sheets varies from 0^@ to 90^@ .Show graphically the variation of he intensity of light transmitted by P_1 and P_2 as a function of the angle theta .Take the incident beam intensity as I_0 . Why does the light from a cleear blue portion of the sky,show a rise and fall on intesnity,when viewed through a polaroid ,which is rotated?

One method of prodocing two in - phase point sources of light for interference is to form two images of a point source by means of the two halves of a lens,which has been split along a diameter[Fig.6.17]. A screen placed perpendicular tot he principal axis and 80 cm from the mage sources.What is the width of central maxima formed on the screen,if the wavelength of the light used is 5.4 xx 10^(-5) cm ?

In figure S is a monochromatic point source emitting light of wavelength lambda=500 nm. A thin lens of circular shape and focal length 0.10 m is cut into two identical halves L_(1) and L_(2) by a plane passing through a doameter. The two halves are placed symmetrically about the central axis SO with a gap of 0.5 mm. The distance along the axis from A to L_(1) and L_(2) is 0.15 m , while that from L_(1) and L_(2) to O is 1.30 m. The screen at O is normal to SO. (a) If the 3^(rd) intensity maximum occurs at point P on screen, find distance OP.