A plane electromagnetic wave is travelling along +y-axis. The value of electric field at a point is $\vec E=12.3\hat i\frac{N}{C}$ The magnitude and direction of magnetic field B at this point is:

$4.1 × 10^{-8} T$, along -z axis

The correct answer is Option (1) → $4.1 × 10^{-8} T$, along -z axis

The magnitude of $\vec B$ is related to $\vec E$ by -

$\vec B=\frac{\vec E}{C}=\frac{12.3}{3×10^8}$

$⇒\vec B=-4.1×10^{-8}T\hat kT$