FIGURE shows the light intensity on a screen $2.5m$behind an aperture. The aperture is illuminated with light of wavelength $620nm$.

a. Is the aperture a single slit or a double slit? Explain.

b. If the aperture is a single slit, what is its width? If it is a double slit, what is the spacing between the slits?

It proposes that things we name particles, such as electrons, mix particle and wave characteristics in some way. This is quantum mechanics well-known wave-particle duality.

Because the intensity of the light fringes drops slowly as the order of the fringes increases, and the fringes are evenly spaced, the given graph displays a pattern of double-slit experiment.

In the double slit experiment, the position of the brilliant fringes can be written as follows:

$y_m=\frac{m\lambda L}{d}$

As a result, the distance between any two brilliant fringes is

$$\begin{gathered} \Delta y=y_{m+1}-y_m \\ =\frac{(m+1)\lambda L}{d}-\frac{m\lambda L}{d} \\ =\frac{\lambda L}{d} \end{gathered}$$

We may calculate the ratio by rearranging this equation.

$d=\frac{\lambda L}{\Delta y}$

The spacing in between two consecutive brilliant fringes is$1$cm, as seen in the diagram. hence

$d=\frac{\left(620\times {10}^{-9}\mathrm{m}\right)\times 2.5\mathrm{m}}{1\times {10}^{-2}\mathrm{m}}$

$d=1.55\times {10}^{-4}\mathrm{m}$