An expression for oscillating electric field in a plane electromagnetic wave is given as Ez = 300 sin(5\( \pi \) \( \times \) 103x \( - \) 3\( \pi \) \( \times \) 1011t) Vm\( - \)1
Then, the value of magnetic field amplitude will be :
(Given : speed of light in Vacuum c = 3 \( \times \) 108 ms\( - \)1)
An expression for oscillating electric field in a plane electromagnetic wave is given as Ez = 300 sin(5\( \pi \) \( \times \) 103x \( - \) 3\( \pi \) \( \times \) 1011t) Vm\( - \)1
Then, the value of magnetic field amplitude will be :
(Given : speed of light in Vacuum c = 3 \( \times \) 108 ms\( - \)1)
Show Hint
- 1 \( \times \) 10\( - \)6 T
- 5 \( \times \) 10\( - \)6 T
- 18 \( \times \) 109 T
- 21 \( \times \) 109 T
The Correct Option is B
Solution and Explanation
Step 2: In a plane EM wave, E0/B0 = wave speed = \(\omega\)/k, so B0 = E0k/\(\omega\).
Step 3: B0 = 300 × 5\(\pi\)×103 / (3\(\pi\)×1011) = (1500/3) × 103-11 = 500 × 10-8 = 5 × 10-6 T.
Answer: (B) 5 × 10-6 T
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