A slit S is illuminated by a monochromatic suorce of light to give two coherent sources P1 and P2. These give a dark band at the point R on the screen as shown in figure.
1. Write the formula to find out bandwidth,
2. What relationship must exist between the length P1R and P2R?
3. Can interference fringes be produced by using two identical bulbs?
4. If the distance between P1 and P2 is 1 mm and the screen is placed in 1m away, what is the fringe separation for a light of wavelength 5 × 10-7 m?