91影视

$\mathrm{位}=470\mathrm{nm}\left(\frac{{10}^{鈥�9}\mathrm{m}}{1\mathrm{nm}}\right)=4.{70}^{,}{10}^{鈥�7}\mathrm{m}$

The wavelength of the blue light is

The order of maximum is 1.

The angle at which the first-order maximum is observed ${}_{\mathbf{25}\mathbf{.}{\mathbf{0}}^{\mathbf{鈭�}}}$

The equation of the constructive interference can be expressed as

$\mathrm{d}\mathrm{蝉颈苍胃}=\mathrm{尘位}$鈥︹赌︹赌︹赌︹赌︹赌︹赌�(1)

Where, $d,位,胃$and m is the separation between slits, the wavelength of the incident light, and the angle made with the maximum and order of maximum, respectively.

Therefore, if we substitute the given data in equation (1) for m=1, we will get,

We then evaluate the number of lines per centimeter, $\mathrm{n}$, using the relation:

$\mathrm{n}=\frac{1.0\mathrm{cm}}{\mathrm{d}}$.

Substitute the value in the above expression, and we get,

$$\begin{gathered} \mathrm{n}=\left(\frac{1.0\mathrm{cm}}{1.12脳{10}^{鈥�6}\mathrm{m}}\right)\left(\frac{1\mathrm{m}}{100\mathrm{cm}}\right) \\ 鈮�8929 \end{gathered}$$

Therefore, the lines for the first-order maximum are ${}^{\mathbf{8929}}$per centimeter.