Suppose the light striking the reflective diffraction grating in Figure 34.13 is white light-that is, light consisting of all the colors of the rainbow. Red light has the longest wavelength of the colors that make up white light; violet has the shortest.

(a) Is the angle at which first-order constructive interference occurs for violet light less than, equal to, or greater than the angle for red light? 

(b) Why are multiple rainbows visible in the reflected light?

Transcribed Image Text:

Figure 34.13 Reflective diffraction grating. path-length difference to observer