Intensity for a point source varies as I∝r21.
Intensity at a distance of 2m, I2=16×10−8×221=4×10−8Wm−2
Similarly, intensity at a distance of 4m, I4=16×10−8×421=1×10−8Wm−2
Required difference, I2−I4=3×10−8Wm−2
A point source is emitting sound waves of intensity 16×10−8Wm−2 at the origin. The difference in intensity (magnitude only) at two points located at a distances of 2m and 4m from the origin respectively will be ________×10−8Wm−2.
Held on 30 Jan 2024 · Verified 6 Jul 2026.
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Work through every JEE Main Waves & Oscillations PYQ, year by year.