Correct Answer - Option 3 : 3.33 × 10
-7 T
Concept:
The intrinsic impedance of the wave is defined as the ratio of the electric field and the magnetic field phasor (complex amplitude), i.e.
\(η =\frac{E}{H}\)
For free-space, the intrinsic impedance is a real quantity, i.e.
η = η0 = 120π
Analysis:
E = Emax sin(Kx - ωt)
With Emax = 100 N/C, the magnetic field will be:
With \(η =\frac{E}{H}\):
\(H =\frac{E}{\eta}\)
\(H =\frac{100}{120\pi}A/m\)
B = μ0 H
\(B=4\pi × 10^{-7}× \frac{100}{120\pi }\)
B = 3.33 × 10-7 T