Fraunhofer diffraction pattern of a single slit is obtained in the focal plane of the lens of focal length 1 m . If the third minimum is formed at a distance of 5 mm from the central maximum and wavelength of light used is 5000 overset° A , then the width of the slit will be

Question

Fraunhofer diffraction pattern of a single slit is obtained in the focal plane of the lens of focal length 1 m . If the third minimum is formed at a distance of 5 mm from the central maximum and wavelength of light used is 5000 overset° A , then the width of the slit will be (A) 0.02cm (B) 0.03 cm (C) 0.04 cm (D) 1 cm

Tardigrade Admin · Accepted Answer

Using asin θ =nλ Or a . (x/f)=3λ or a=(3 λ . f/x) =(3 × 500 × 10- 9 × 1/5 × 10- 3)=3× 10- 4 m=0.03 cm

Q. Fraunhofer diffraction pattern of a single slit is obtained in the focal plane of the lens of focal length $1 m$ . If the third minimum is formed at a distance of $5 mm$ from the central maximum and wavelength of light used is $5000 A^{\circ}$ , then the width of the slit will be

$0.02 c m$

$0.03 c m$

$0.04 c m$

$1 c m$

Using $a s in θ = nλ$
Or $a . \frac{x}{f} = 3 λ$ or $a = \frac{3 λ . f}{x}$
$= \frac{3 \times 500 \times 1 0 ^{- 9} \times 1}{5 \times 1 0 ^{- 3}} = 3 \times 1 0^{- 4} m = 0.03 c m$

Q. Fraunhofer diffraction pattern of a single slit is obtained in the focal plane of the lens of focal length 1m . If the third minimum is formed at a distance of 5mm from the central maximum and wavelength of light used is 5000A∘ , then the width of the slit will be

0.02cm

0.03cm

0.04cm

1cm