Question

Consider an n-slit grating with slit widths (a) and separations (8a), find the ratio of intensities between the 4th and 2nd order maxima.

a) 1/81
b) 1/64
c) 1/16
d) 1/8

Answer 1

The ratio of intensities between the 4th and 2nd order maxima in an n-slit grating can be found by considering the number of slits and their widths. In this case, the ratio is 4.

Step-by-step explanation:

In a grating, the ratio of intensities between the 4th and 2nd order maxima can be found by considering the number of slits and their widths. In this case, the grating has a slit width (a) and a separation of (8a). The intensity at each order of the maxima in a grating can be given as (Intensity = (Number of slits)^2*sin^2(theta)/width of the slit)^2. Therefore, the ratio of intensities between the 4th and 2nd order maxima will be (4^2*sin^2(theta))/(2^2*sin^2(theta)) = (16/4) = 4. Therefore, the correct option is d) 1/8.