A person standing at a distance of 6m from a source of sound receives sound wave in two ways, one directly from the source and other after reflection from a rigid boundary as shown in the figure. The maximum wavelength for which, the person will receive maximum sound intensity, is

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G1 Physics · Accepted Answer

Step 1: Use superposition at the boundary. Reflection from a denser/fixed boundary introduces phase reversal; from a free boundary it does not. Step 2: Energy ratio gives amplitude ratio through I ∝ A² for waves in the same medium. Step 3: Combine incident, reflected and transmitted waves with the proper direction. Final: A: 4 m.