Two slits are separated by a distance of 0.5 mm and illuminated with light of wavelength λ = 6000 mathringA. If the screen is placed at 2.5 m from the slits. The distance of the third bright fringe from the centre will be

Question

Two slits are separated by a distance of 0.5 mm and illuminated with light of wavelength λ = 6000 mathringA. If the screen is placed at 2.5 m from the slits. The distance of the third bright fringe from the centre will be (A) 1.5 mm (B) 3 mm (C) 6 mm (D) 9 mm

Tardigrade Admin · Accepted Answer

Distance of nth bright fringe from the centre, xn=(nDλ/d) So, x3=(3×2.5×6000×10-10/0.5×10-3) =9×10-3 m=9 mm

Q. Two slits are separated by a distance of 0.5 mm and illuminated with light of wavelength $λ$ = 6000 $\overset{˚}{A}$ . If the screen is placed at 2.5 m from the slits. The distance of the third bright fringe from the centre will be

1.5 mm

3 mm

6 mm

9 mm

Distance of n^th bright fringe from the centre,
$x_{n} = \frac{n D λ}{d}$
So, $x_{3} = \frac{3 \times 2.5 \times 6000 \times 1 0 ^{- 10}}{0.5 \times 1 0 ^{- 3}}$
$= 9 \times 1 0^{- 3} m = 9 mm$

Q. Two slits are separated by a distance of 0.5 mm and illuminated with light of wavelength λ = 6000 A˚. If the screen is placed at 2.5 m from the slits. The distance of the third bright fringe from the centre will be