Two small speakers are powered by the same amplifier. The speakers are fixed at a separation of 2 m inside a box. A microphone (M) placed at a distance of 4 m from the midpoint of line joining the speakers (see figure (a)) records an intensity maxima. The box is slowly rotated till the two speakers and the microphone fall in a straight line (figure(b)). Including the initial and the final positions, a total of 6 positions (orientations) were observed for the box which produced an intensity maxima at the microphone. Find the wavelength λ (in m) of the sound. What is the value of 5λ? While rotating the box, its centre O remains unmoved.

Question

Two small speakers are powered by the same amplifier. The speakers are fixed at a separation of 2 m inside a box. A microphone (M) placed at a distance of 4 m from the midpoint of line joining the speakers (see figure (a)) records an intensity maxima. The box is slowly rotated till the two speakers and the microphone fall in a straight line (figure(b)). Including the initial and the final positions, a total of 6 positions (orientations) were observed for the box which produced an intensity maxima at the microphone. Find the wavelength λ (in m) of the sound. What is the value of 5λ? While rotating the box, its centre O remains unmoved.