Question

If the magnetic field of a plane electromagnetic wave is given by (The speed of light = $3 \times 10^8 \; /m/s$)
$B = 100 \times 10^{-6} \; \sin [ 2 \pi \times 2 \times 10^{15} ( t - \frac{x}{c} ) ] $ then the maximum electric field associated with it is :

• A. $ 4 \times 10^4 \; N / C$
• B. $ 4.5 \times 10^4 \; N / C$
• C. $ 6 \times 10^4 \; N / C$
• D. $ 3 \times 10^4 \; N / C$

Answer 1

Answer: (D)

$E_0 = B_0 \times C$
$= 100 \times 10^{-6} \times 3 \times 10^8$
$= 3 \times 10^4 \; N/C$
$\therefore $ correct answer is $3 \times 10^4 \; N/C$