Question

`S_1` and `S_2` are two coherent sources of sound having no initial phase difference. The velocity of sound is `330m//s`. No minimal will be formed on the line passing through `S_2` and perpendicular to the line jouning `S_1` and `S_2`. If the frequency of both the sources is:
A. `50Hz`
B. `60Hz`
C. `70Hz`
D. `80Hz`

Answer 1

Correct Answer - A
For minimum `Delta x=(2n-1)(lamda)/(2)`
between maximum possible path difference `=`distance beween the sources `=3m`
For no minimum `(lamda)/(2)gt3implieslamdagt6`
`:. f=(V)/(lamda)lt(330)/(6)=55`.
if `:. flt55Hz` no minimum will occur.