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A plane electromagnetic wave of frequency 50 MHz travels in free space along the positive x-direction. At a particular point in space and time, E = 6.3 ĵ V/m. The corresponding magnetic field B, at that point will be:

1. 18.9 × 10⁻⁸ k̂ T
2. 2.1 × 10⁻⁸ k̂ T
3. 6.3 × 10⁻⁸ k̂ T
4. 18.9 × 10⁻⁸ k̂ T

Correct answer: 2.1 × 10⁻⁸ k̂ T

Solution

The correct option is derived from the relationship between the electric field and magnetic field in an electromagnetic wave, given by the equation B = E/c, where c is the speed of light. With E = 6.3 V/m and c approximately 3 x 10⁸ m/s, the calculated magnetic field is 2.1 x 10⁻⁸ T, which matches the correct answer.

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