Chapter 19.1, Problem 3PP

To determine

The distance between the slits.

Answer to Problem 3PP

  $9.66\times {10}^{-6}\text{m}$

Explanation of Solution

Given:

The wavelength of the laser light, $\lambda =632.8\text{nm}$

The distance of the screen from the slits, $L=1.000\text{m}$

The distance of the first-order bright band from the central line, $x=65.5\text{mm}$

Formula used:

For first order bright band, wavelength can be obtained by using:

  $\lambda =\frac{xd}{L}$

Where,

x is the distance of first bright band from the central line on the screen.

d is the distance between slits

L is the distance of screen from the slits.

Calculation:

Using the above mentioned formula and the given values, the distance between the slits will be,

  $\begin{array}{c}\lambda =\frac{xd}{L}\\ 632.8\times {10}^{-9}=\frac{\left(65.5\times {10}^{-3}\right)d}{1.000}\\ d=9.66\times {10}^{-6}\text{m}\end{array}$

Conclusion:

Hence, the distance between the slits is $9.66\times {10}^{-6}\text{m}$ .