A narrow tube is bend in the form of a circle of radius R, as shown in the figure. Two small holes S and D are made in the tube at the positions right angle to each other. A source placed at S generated a wave of intensity `I_(0)` which is equally divided into two parts : One part travels along the longer path, while the other travels along the shorter path. Both the parts wave meet at the point D where a detector is placed.

The maximum value of `lamda` to produce a maxima at D is given by :-

Options

A. `piR`
B. `2piR`
C. `(piR)/(2)`
D. `(3piR)/(2)`

Answer

A