two sound sources `S_(1)` and `S_(2)` are kept symmetrically about the centre of a circle as shown. The circle is divided is 4 parts. Both the sources are separated by a `8lamda//3` distance.
Where `lamda` is wavelength of sound emitted by the sources. A detector is moving around the circle. How many times it will detect a minima in II part if `S_(1)` is leading `S_(2)` by phase of `2pi//3`?

Options

A. 3
B. 4
C. 2
D. 5

Answer

C

Explanation

Phase difference equivalent to `(8lamda)/(3)` path difference
`(2pi)/(lamda)xx(8lamda)/(3)=(16pi)/(3)`
Part I,II,III and IV will be 2,2,3 and 3 minima respectively