The magnetic field in a travelling electromagnetic wave has a peak value of 20 nT. The peak value of electric field strength (in volt `m^(-1)` ) is

Explanation

To find the peak value of the electric field strength (E₀) in an electromagnetic wave when the peak value of the magnetic field (B₀) is given, we can use the relationship between the electric field and magnetic field in electromagnetic waves. The relationship is given by the equation:

\[ E₀ = c \cdot B₀ \]

where:
- \( E₀ \) is the peak electric field strength in volts per meter (V/m),
- \( B₀ \) is the peak magnetic field strength in tesla (T),
- \( c \) is the speed of light in vacuum, approximately \( 3 \times 10^8 \) meters per second (m/s).
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