In an interference experiment, third bright fringe is obtained at a point on the screen with a light of 700 nm . What should be the wavelength of the light source in order to obtain 5th bright fringe at the same point ?

Question

In an interference experiment, third bright fringe is obtained at a point on the screen with a light of 700 nm . What should be the wavelength of the light source in order to obtain 5th bright fringe at the same point ? (A)  500 nm  (B)  630 nm  (C)  750 nm  (D)  420 nm

Tardigrade Admin · Accepted Answer

n1 λ1= n2 λ2 ⇒ 3 × 700=5 × λ2 ⇒ λ2=420 nm

Q. In an interference experiment, third bright fringe is obtained at a point on the screen with a light of $700 nm$ . What should be the wavelength of the light source in order to obtain $5 t h$ bright fringe at the same point ?

$500 nm$

$630 nm$

$750 nm$

$420 nm$

$n_{1} λ_{1} = n_{2} λ_{2}$
$\Rightarrow 3 \times 700 = 5 \times λ_{2}$
$\Rightarrow λ_{2} = 420 nm$

Q. In an interference experiment, third bright fringe is obtained at a point on the screen with a light of 700nm . What should be the wavelength of the light source in order to obtain 5th bright fringe at the same point ?

500nm

630nm

750nm

420nm