Green light of wavelength 550 nm passes through a diffraction grating with a slit spacing of 0.001 mm and makes an interference pattern on the wall. How many bright fringes will be seen? А. 1 В. 3 С. 5 D. 7

m, and d= 3.00 x 10 m. (B) Determine the distance between adjacent bright fringes. Use the bright fringe equation again to find the distance between any adjacent bright fringes (here, those characterized by m and m + 1). AL AL (m+ 1) - AL Ay = y+1 m%3D (5.63 x 107 m)(1.20 m) - 2.25 cm 3.00 x 105 m LEARN MORE REMARKS This calculation depends on the angle 0 being small because the small angle approximation was implicitly used. The measurement of the position of the bright fringes yields the wavelength of light, which in turn is a signature of atomic processes, as is discussed in the chapters on modern physics. This kind of measurement therefore helped open the world of the atom. QUESTION Which of the following make the separation between fringes greater in the two slit interference experiment? (Select all that apply.) O Larger separation of the two slits. O Narrower slits. Wider slits. O Smaller separation of the two slits. PRACTICE IT Use the worked example above to help you solve this…

Question A2 Red light of vacuum wavelength 650 nm is travelling in a non-magnetic dielectric glass of refrac- tive index ng = 1.60. Calculate the impedance of the glass, the wavelength of light in the glass, and the critical angle 0c for total internal reflection at a glass-air interface. Question A3 Light is incident from air onto a horizontal surface of water of refractive index nw = 1.33. Calculate the Brewster angle at which the reflectance for the TM polarisation is zero. Also, cal- culate the power reflection coefficient RTE for TE-polarised light incident at this Brewster angle.

Monochromatic light (λ = 500 nm) is incident on a soap bubble (n = 1.40). How thick is the bubble (in nm) if constructive interference occurs in the reflected light? a. b. C. d. 102 89 54 138