Two waves are represented by: `y_(1)=4sin404 pit` and `y_(2)=3sin400 pit`. Then :

Options

A. Beat frequency is 4 Hz and the ratio of maximum to minimum intensity is 49 : 1
B. Beat frequency is 2 Hz and the ratio of maximum to minimum intensity is 49 :1
C. Beat frequency is 2 Hz and the ratio of maximum to minimum intensity is 1:49
D. Beat frequency is 4 Hz and the ratio of maximum to minimum intensity is 1:49

Answer

B

Explanation

`y_(1)=4sin404pit , y_(2)=3sin400pit`
Beat frequency = `f_(1)-f_(2)=(404pi)/(2pi)-(400pi)/(2pi)=2Hz`
`(I_(max))/(I_(min))=((A_(1)+A_(2))^(2))/((A_(1)-A_(2))^(2))=((4+3)^(2))/((4-3)^(2))=(49)/(1)`