Question

A beam of laser light of wavelength 632.8 nm falls on a thin slit 3.50×10⁻³ mm wide.

After the light passes through the slit, at what angles relative to the original direction of the beam is it completely cancelled when viewed far from the slit?

Type absolute values of the three least angles separating them with commas.

Answer 1

Given;-

$\lambda$ = 632.8 x 10^-9 m

d = 3.50 x 10^-6 m

$\Theta$ = sin^-1(m $\lambda$ /d)

whrere m = 1,2,3,4...

$\Theta$ 1 = sin^-1(1 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 1 = 10.42 degree

$\Theta$ 2 = sin^-1(2 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 2 = 21.2 degree

$\Theta$ 3 = sin^-1(3 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 3 = 32.82 degree

$\Theta$ 1, $\Theta$ 2, $\Theta$ 3 = 10.24 degree, 21.2 degree, 32.82 degree

Answer 2

Given;-

$\lambda$ = 632.8 x 10^-9 m

d = 3.50 x 10^-6 m

$\Theta$ = sin^-1(m $\lambda$ /d)

whrere m = 1,2,3,4...

$\Theta$ 1 = sin^-1(1 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 1 = 10.42 degree

$\Theta$ 2 = sin^-1(2 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 2 = 21.2 degree

$\Theta$ 3 = sin^-1(3 x 632.8 x 10^-9 / 3.50 x 10^-6)

$\Theta$ 3 = 32.82 degree

$\Theta$ 1, $\Theta$ 2, $\Theta$ 3 = 10.24 degree, 21.2 degree, 32.82 degree