A tiny vibrating source sends waves uniformly in all directions. An area of 3.25 cm2 on a sphere of radius 2.50 m centered on the source receives energy at a rate of 4.20 J/s
(a) What is the intensity of the waves at 2.50 m from the source and at 10.0 m from the source?
(b) At what rate is energy leaving the vibrating source of the waves?
What will be an ideal response?
Answer:
(a) 12,900 W/m2 (at 2.50 m), 808 W/m2 (at 10.0 m)
(b) 1.01 × 106 W
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?
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