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

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

Correct answer: 6 V/m

Solution

The relationship between the peak values of the electric field (E) and magnetic field (B) in an electromagnetic wave is given by the equation E = cB, where c is the speed of light. Using the peak magnetic field value of 20 nT and the speed of light, we find that the corresponding peak electric field strength is 6 V/m.

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