Question

The maximum electric field in a plane electromagnetic wave is$900N{C}^{-1}$. The wave is going in$x$ -direction and the electric field is in the $y$-direction. The maximum magnetic field in the wave is$\_\_\_\_\_\_\_\_\_\_\_\_\_T.$

• A. $3x{10}^{-8}$
• B. $3x{10}^{-6}$
• C. $27x{10}^{-6}$
• D. $27x{10}^{10}$

Answer 1

The correct option is B

$3x{10}^{-6}$

Step 1. Given data:

The maximum electric field in a plane electromagnetic wave$E_0=900N{C}^{-1}$

The direction of the wave is $=x$

The direction of the electric field $=y$

Step 2. Formula used:

The maximum magnetic field can be expressed as,

$B_0=\frac{E_0}{c}$ (Where$B_0=$ Maximum magnetic field, $c=$Speed of light in vacuum)

Step 3. Calculating the maximum magnetic field:

The maximum value of the magnetic field,

$$\begin{gathered} B_0=\frac{E_0}{c} \\ =\frac{900}{3\times {10}^8}T \\ =3\times {10}^{-6}T \end{gathered}$$

Thus, the maximum magnetic field is $3x{10}^{-6}T$.

Hence, option B is the correct answer.