Light of wavelength λ is incident on a slit of width d. The resulting diffraction pattern is observed on a screen at a distance D. The linear width of the principal maximum is equal to the width of the slit, if D equals

Question

Light of wavelength λ is incident on a slit of width d. The resulting diffraction pattern is observed on a screen at a distance D. The linear width of the principal maximum is equal to the width of the slit, if D equals (A) (d2/2 λ) (B) (d/λ) (C) (2 λ2/d) (D) (2 λ/d)

Tardigrade Admin · Accepted Answer

The linear width of central principal maximum =(2 λ D/d) If it is equal to width of slit (d), then (2 λ D/d)=d or D=(d2/2 λ)

Q. Light of wavelength $λ$ is incident on a slit of width $d$ . The resulting diffraction pattern is observed on a screen at a distance $D$ . The linear width of the principal maximum is equal to the width of the slit, if $D$ equals

$\frac{d ^{2}}{2 λ}$

$\frac{d}{λ}$

$\frac{2 λ ^{2}}{d}$

$\frac{2 λ}{d}$

The linear width of central principal maximum
$= \frac{2 λ D}{d}$
If it is equal to width of slit $(d)$ , then
$\frac{2 λ D}{d} = d$
or $D = \frac{d ^{2}}{2 λ}$

Q. Light of wavelength λ is incident on a slit of width d. The resulting diffraction pattern is observed on a screen at a distance D. The linear width of the principal maximum is equal to the width of the slit, if D equals

2λd2​

λd​

d2λ2​

d2λ​