Question 141: Wave Optics

Question

In a double-slit experiment, green light (5303$$\mathop A\limits^ \circ  $$) falls on a double slit having a separation of 19.44 $$\mu $$m and awidht of 4.05 $$\mu $$m. The number of bright fringes between the first and the second diffraction minima is :

Accepted Answer

For diffraction
location of 1
st
minima
y
1
= $${{D\lambda } \over a}$$ = 0.2469 D$$\lambda $$
location of 2
nd
minima
y
2
= $${{2D\lambda } \over a}$$ = 0.4938 D$$\lambda $$
Now for interference
Path difference at P.
$${{dy} \over D}$$ = 4.8$$\lambda $$
path difference at Q
$${{dy} \over D}$$ = 9.6$$\lambda $$
So orders of maxima in between P & Q is 5, 6, 7, 8, 9
So 5 bright fringes all present between P & Q.

Answer

04

Answer

05

Answer

10

Answer

09

Wave Optics

In a double-slit experiment, green light (5303$\mathop A\limits^ \circ ) falls on a double slit having a separation of 19.44 \mu m and awidht of 4.05 \mu $m. The number of bright fringes between the first and the second diffraction minima is :

Choose the correct answer: