1. Blue light of wavelength passes through a single slit of width d and forms a diffraction pattern on a screen. If we replace the blue light by red light of wavelength 2λ we can retain the original diffraction pattern if we change the slit width
(a) To d 4.
(b) To d 2.
(c) Not at all.
(d) To 2d.
(e) To 4d.
2. Imagine holding a circular disk in a beam of monochromatic light (Fig. 24-56). If diffraction occurs at the edge of the disk, the center of the shadow is
(a) Darker than the rest of the shadow.
(b) A bright spot.
(c) Bright or dark, depending on the wavelength.
(d) Bright or dark, depending on the distance to the screen.

Transcribed Image Text:

Disk Shadow n Screen