51. The intensity of electromagnetic energy 3 m from the point source is 100 W/m2. What is theintens
問題詳情
51. The intensity of electromagnetic energy 3 m from the point source is 100 W/m2. What is theintensity 30 m away? (A) 1000 W/m2 (B) 100 W/m2 (C) 10 W/m2 (D) 1 W/m2 (E) 0.1 W/m2