If the amplitude ratio of two sources producing interference is 3: 5 , the ratio of intensities at maxima and minima is

Question

If the amplitude ratio of two sources producing interference is 3: 5 , the ratio of intensities at maxima and minima is (A) 25: 16 (B) 5: 3 (C) 16: 1 (D) 25: 9

Tardigrade Admin · Accepted Answer

a1: a2=3: 5 Let a1=3 a and a2=5 a (I max /I min )=((a1+a2)2/(a1-a2)2) =((3 a+5 a)2/(3 a-5 a)2) =(64/4)=(16/1)

Q. If the amplitude ratio of two sources producing interference is $3 : 5$ , the ratio of intensities at maxima and minima is

25 : 16

5 : 3

16 : 1

25 : 9

$a_{1} : a_{2} = 3 : 5$
Let $a_{1} = 3 a$ and $a_{2} = 5 a$
$\frac{I _{m a x}}{I _{m i n}} = \frac{( a _{1} + a _{2} ) ^{2}}{( a _{1} - a _{2} ) ^{2}}$
$= \frac{( 3 a + 5 a ) ^{2}}{( 3 a - 5 a ) ^{2}}$
$= \frac{64}{4} = \frac{16}{1}$

Q. If the amplitude ratio of two sources producing interference is 3:5 , the ratio of intensities at maxima and minima is