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The magnetic field in a traveling electromagnetic wave has a peak value of 20 nT. The peak value of electric field strength is -

1. 9 V/m
2. 12 V/m
3. 3 V/m
4. 6 V/m

Correct answer: 6 V/m

Solution

The relationship between the peak values of the electric field and magnetic field in an electromagnetic wave is given by the equation E = cB, where E is the electric field strength, B is the magnetic field strength, and c is the speed of light. Given the peak magnetic field of 20 nT, the corresponding peak electric field strength calculates to 6 V/m.

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