What will be the angle of diffraction for the first secondary maximum due to diffraction at a single slit of width 0.4 mm, using light of wavelength 4000 mathringA ?

Question

What will be the angle of diffraction for the first secondary maximum due to diffraction at a single slit of width 0.4 mm, using light of wavelength 4000 mathringA ? (A)  1.0× 10-4 rad (B)  0.5× 10-4 rad (C)  0.15× 10-3 rad (D)  1.5× 10-3 rad

Tardigrade Admin · Accepted Answer

Angle of diffraction for the secondary maxima θ=(3/2) × (λ/a) =(3/2) × (4000 × 10-10/0.4 × 10-3) =(30/2) × 10-4=15 × 10-4 =1.5 × 10-3 rad

Q. What will be the angle of diffraction for the first secondary maximum due to diffraction at a single slit of width $0.4 mm$ , using light of wavelength $4000 \overset{˚}{A}$ ?

$1.0 \times 1 0^{- 4}$ rad

$0.5 \times 1 0^{- 4}$ rad

$0.15 \times 1 0^{- 3}$ rad

$1.5 \times 1 0^{- 3}$ rad

Angle of diffraction for the secondary maxima
$θ = \frac{3}{2} \times \frac{λ}{a}$
$= \frac{3}{2} \times \frac{4000 \times 1 0 ^{- 10}}{0.4 \times 1 0 ^{- 3}}$
$= \frac{30}{2} \times 1 0^{- 4} = 15 \times 1 0^{- 4}$
$= 1.5 \times 1 0^{- 3} r a d$

Q. What will be the angle of diffraction for the first secondary maximum due to diffraction at a single slit of width 0.4mm, using light of wavelength 4000A˚ ?

1.0×10−4 rad

0.5×10−4 rad

0.15×10−3 rad

1.5×10−3 rad