NEET 2017 · PhysicsE and B relationPrevious Year Question
In an electromagnetic wave in free space the root mean square value of the electric field is E_rms = 6 V/m. The peak value of the magnetic field is
Answer: (B) 2.83 ×10⁻⁸ T. Answer: (B) 2.83 ×10⁻⁸ T.
- A.1.41 ×10⁻⁸ T
- B.2.83 ×10⁻⁸ T✓
- C.0.70 ×10⁻⁸ T
- D.4.23 ×10⁻⁸ T
Correct Answer
(B) 2.83 ×10⁻⁸ T
Solution & Explanation
Answer: (B) 2.83 ×10⁻⁸ T. In an EM wave E = cB at every instant, so B_rms = E_rms/c, and the peak value B₀ = √2 · B_rms.
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