Question

Light from an argon laser strikes a diffraction grating that has 7,735 grooves per centimeter. The central and first-order principal maxima are separated by 0.488 m on a wall 1.73 m from the grating. Determine the wavelength of the laser light.

Answer 1

Answer:

wavelength of the laser light is 351nm

Explanation:

The split seperation is

d = 0.01 / 7735

= 1293nm

The angle of the first order maxima

θ = tan⁻¹ (0.488/1.73)

= 15.75°

we have,

$sin \theta = \frac{m \lambda}{d} \\\lambda = \frac{d sin \theta}{m} \\\lambda = \frac{1293 \times sin15.75}{1} \\= 350.97nm$

≅ 351nm

wavelength of the laser light is 351nm