⚛️ Physics · Electromagnetic Waves · NEET & JEE

A plane electromagnetic wave has a peak electric field of 48 V/m. Its average intensity (S = ½ε0cE02) is approximately:

Answer: 3.1 W/m 2.

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.

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A plane electromagnetic wave has a peak electric field of 48 V/m. Its average intensity (S = &frac12;&epsilon;<sub>0</sub>cE<sub>0</sub><sup>2</sup>) is approximately:

Concept context

More Electromagnetic Waves questions

A plane electromagnetic wave has a peak electric field of 48 V/m. Its average intensity (S = ½ε<sub>0</sub>cE<sub>0</sub><sup>2</sup>) is approximately: