Answer: 3.1 W/m2.
- A 6.1 W/m2
- B 1.5 W/m2
- C 12.2 W/m2
- D 3.1 W/m2
Correct answer: D. 3.1 W/m2
Explanation: S = ½ × 8.85 × 10-12 × 3 × 108 × 482 ≈ 3.1 W/m2.
In an electromagnetic wave, the oscillating electric field (E) and magnetic field (B) are perpendicular to each other and to the direction the wave travels - a purely transverse wave that needs no medium, unlike sound.
Concept context
Maxwell's equations, EM spectrum, properties, and applications of each band.