Answer: 868 V/m.
- A 868 V/m
- B 1000 V/m
- C 3 × 10⁸ V/m
- D 30 V/m
Correct answer: A. 868 V/m
Explanation: I = ½cε_0 E<sub>0</sub>². E<sub>0</sub> = √(2I/(cε_0)) = √(2×1000/(3×10⁸×8.85×10⁻¹²)) = √(2000/2.65×10⁻³) = √(7.54×10⁵) ≈ 868 V/m.
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.