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A radio station operates at a frequency of 830 kHz. At a given point away from the antenna, the magnetic field amplitude is 4.82 × 10⁻¹¹ T. The corresponding electric field strength and wavelength are, respectively,

1. 0.014 N/C, 36 m
2. 0.14 N/C, 36 m
3. 0.14 N/C, 360 m
4. 0.014 N/C, 360 m

Correct answer: 0.014 N/C, 360 m

Solution

The electric field strength can be calculated using the relationship between the magnetic field and the electric field in electromagnetic waves, where E = cB. Given the magnetic field amplitude, the electric field strength is found to be 0.014 N/C. The wavelength is determined using the frequency and the speed of light, resulting in 360 m.

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