Question

3)A 680 nm laser illuminates a double-slit apparatus with a slit separation distance of 7.83 μm. On the viewing screen, you measure the distance from the central bright fringe to the 2nd bright fringe to be 88.2 cm. How far away (in meters) is the viewing screen from the double slits?

4) A 600 nm laser illuminates a double-slit apparatus with a slit separation distance of 3.55 μm. The viewing screen is 1.50 meters behind the double slits. What is the distance (in meters) from the central bright fringe to the 3rd dark fringe?

5) A 600 nm laser illuminates a double-slit apparatus with a slit separation distance of 3.55 μm. The viewing screen is 1.50 meters behind the double slits. What is the distance (in cm) between the 2nd and 3rd dark fringes?

Answer 1

3) Distane of n-th fringe from the central fringe is given by the following expression: AL Y = na Here, y, is the distance of fringe from the central fringe, n is the order of fringe, 2 is the wavelength, L is disrance of screem from the slit, and d is the distance between the slits. Substitute values and calculate distance of screen from the slite. y,=n L = yd (88.2 cm) (7.83 um (2)(680 nm) (88.2x10-2 m)(7.83x10 m) (2)(680x109 m) = 5.08 m