91影视

The essential condition for the occurrence of constructive interference at any point is that the path difference between the rays, moving towards the point, is equal to the integral multiple of the wavelength of light used.

Similarly, for destructive interference, the path difference should be half-integral multiple of the wavelength of light.

The path difference in multiple diffractions is equal to $m位$i.e.,$未=m位$.

By trigonometry, $\mathrm{未}=\mathrm{d}\mathrm{蝉颈苍胃}$. Now,

$$\begin{gathered} 蠒=\frac{2蟺}{位}未 \\ =\frac{2蟺}{位}d\sin 胃 \\ =\frac{2蟺}{位}m位 \\ =2\mathrm{蟺尘}\left(\mathrm{m}=0.+2,+3,\right) \end{gathered}$$

This equation will work only for special cases where$未$ is an integer multiple of the wavelength and the value of$蠒$will not be limited to these values

Hence, the value of$蠒$can be anything but we need to consider only those for which$未$ is an integral multiple of $位$,.