Separation between the first maximum and fifth minimum of a YDSE pattern is 7mm and the slits are separated by 0.15mm with the screen 50cm from the slits, then the wavelength of the light used is

Question

Separation between the first maximum and fifth minimum of a YDSE pattern is 7mm and the slits are separated by 0.15mm with the screen 50cm from the slits, then the wavelength of the light used is (A) 600nm (B) 525mm (C) 467nm (D) 420nm

Tardigrade Admin · Accepted Answer

There are three and a half fringes from first maxima to fifth minima as shown. <img class="img-fluid question-image" alt="Solution" src="https://cdn.tardigrade.in/q/nta/p-aq2hzdpnpvwqzzts.jpg" /> ⇒ β =(7 m m/3 . 5)=2mm⇒ λ =(β d/D)=600nm

Q. Separation between the first maximum and fifth minimum of a YDSE pattern is $7 mm$ and the slits are separated by $0.15 mm$ with the screen $50 c m$ from the slits, then the wavelength of the light used is

$600 nm$

$525 mm$

$467 nm$

$420 nm$

There are three and a half fringes from first maxima to fifth minima as shown.

$\Rightarrow β = \frac{7 mm}{3.5} = 2 mm \Rightarrow λ = \frac{β d}{D} = 600 nm$

Q. Separation between the first maximum and fifth minimum of a YDSE pattern is 7mm and the slits are separated by 0.15mm with the screen 50cm from the slits, then the wavelength of the light used is

600nm

525mm

467nm

420nm