The distance between the two identical speakers shown in Fig. 14.3.3 are 4.00m. They are driven by the same osicllator. Initially a listner stays at L at a distance 8.0 m from the centre of the line connecting the two speakers. The listner then walks to the point A where AL=0.4m. The first minium is sound intensity in heard just the listener reaches the point A. Find the frequency of the oscillator. Speed of sound in air is 340 m/s.

Explanation

To solve the problem step by step, we will follow the reasoning laid out in the video transcript while ensuring clarity and precision in our calculations.

### Step 1: Understand the Setup
We have two identical speakers that are 4.00 m apart, and they are driven by the same oscillator. A listener starts at point L, which is 8.0 m away from the midpoint between the two speakers, and then moves to point A, where the distance AL = 0.4 m.

### Step 2: Identify the Condition for First Minimum
The first minimum in sound intensity occurs when the path difference between the sound waves from the two speakers to the listener is equal to half the wavelength (λ/2). This is the condition for destructive interference.

...