Question

A plane Electro-Magnetic wave travels in free space along $X-axis$. At a particular point in space, the electric field along $Y-axis$ is $9.3V{m}^{-1}$. Magnetic induction is

• A. $3.1\times {10}^{-8}T$
• B. $3\times {10}^{-5}T$
• C. $3\times {10}^{-6}T$
• D. $9.3\times {10}^{-6}T$
• E. $3.1\times {10}^{-7}T$

Answer 1

The correct option is A

$3.1\times {10}^{-8}T$

Step 1. Given Data:

Electric Field $E=9.3V{m}^{-1}$

Step 2. Find magnetic induction:

If $c$ is the speed of light and $B$ is the magnetic induction then,

$c=\frac{E}{B}$

$\Rightarrow$ $B=\frac{E}{c}$

$=\frac{9.3}{3\times {10}^8}$

$=3.1\times {10}^{-8}T$

Hence option (A) is correct.