Question

In an electromagnetic wave, the magnitude of electric and magnetic fields are 100 V/m and 0.265 A/m. The maximum energy flow is

• A. (A) 26.5 W/m2
• B. (B) 36.5 W/m2
• C. (C) 46.7 W/m2
• D. (D) 765 W/m2

Answer 1

Answer: (A)

(A) 26.5 W/m2

Answer 2

Explanation:
Given:Electrical field E = 100 V/mMagnetic field B = 0.265 A/mThe energy flow is given by the Poynting vector S→=E→×B→⇒S=EBsin⁡∅⇒S=EB[∅=90∘, as E and B are perpendicular to each other]⇒S=100V/m×0.265A/m⇒S=26.5W/m2Hence, the correct option is (A).