Question : Two slits in YDSE have width in the ratio 1:25. The ratio of intensity at the maxima and minima in the interference pattern Imax/Imin is
a) 4/9
b) 9/4
c) 121/49
d) 49/121
Doubt by Angad
Solution :
ω1/ω2 = 1/25
(a1/a2)²=1/25
a1/a2 = √(1/25)
a1/a2 = 1/5
r = 1/5
a1/a2 = 1/5
r = 1/5
We know,
Imax/Imin=(r+1)²/(r-1)²
Imax/Imin=(1/5+1)²/(1/5-1)²
Imax/Imin = (6/5)²/(-4/5)²
Imax/Imin= 9/4
Imax/Imin=(r+1)²/(r-1)²
Imax/Imin=(1/5+1)²/(1/5-1)²
Imax/Imin = (6/5)²/(-4/5)²
Imax/Imin= 9/4
Hence, b) 9/4 would be the correct option.
