A Helium-Neon Laser and Diffraction Grating Experiment

What is the spacing between the slits of the grating illuminated by the Helium-Neon laser and how is it calculated?

The spacing between the slits of the grating illuminated by the Helium-Neon laser is 102 µm. This spacing can be calculated using the formula d = λy/L, where λ is the wavelength of the Helium-Neon laser, y is the distance between two bright fringes, and L is the distance from the screen to the grating.

Calculation of Spacing Between Slits

The spacing between the slits of the grating illuminated by the Helium-Neon laser can be calculated as follows:

Given:
Wavelength of Helium-Neon laser, λ = 633 nm
Distance between two bright fringes, y = 32 cm
Distance from the screen to the grating, L = 2 m

We know that, Spacing of the grating, d = λy/L
Applying the values in the above formula:
Spacing of the grating, d = (633*10^-9 * 0.32) / 2
d = 1.02*10^-4 m
Therefore, the spacing between the slits of the grating illuminated by the Helium-Neon laser is 102 µm.

Sketch:
To visualize the experiment setup, refer to the accompanying sketch.
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