Answer:
λ ≈ 462 nm
Explanation:
Given:-
- The slit separation, a = 10^-5 m
- The first bright fringe occurs at, y = 0.03 m from central order
- The distance between the screen and slit, L = 0.65 m
Find:-
what is the wavelength of this light?
Solution:-
- The Young's double slit experiment gives us the relation for the interaction of a light with wavelength ( λ ) that pass through 2-slits with separation ( a ) and interfere constructively or destructively at the the screen Hence, forming an interference pattern of bright and dark fringes.
- The relation for separation ( y ) between bright fringes is related to the above mentioned parameters as given below:
y = L*n*λ / a
Where,
n: The order of fringe from central
Re-arrange for wavelength ( λ ).
- The order of first bright fringe is n = 1:
λ = y*a / L
λ = 0.03*0.00001 / 0.65
λ = 4.61538 * 10^-7 m
λ ≈ 462 nm
