CUET · PHYSICS · PYQ PAPER 2025
In a plane electromagnetic wave, the electric field oscillates sinusoidally at a frequency of \( 3 \times 10^{10} \text{ Hz} \) and its amplitude is 30 V/m. The amplitude of the oscillating magnetic field is:
- A \( 1 \times 10^{-7} \text{ T} \)
- B \( 1.5 \times 10^{-7} \text{ T} \)
- C \( 1.5 \times 10^{-8} \text{ T} \)
- D \( 1 \times 10^{-8} \text{ T} \)
Answer & Solution
Correct Answer
(A) \( 1 \times 10^{-7} \text{ T} \)
Step-by-step Solution
Detailed explanation
\( B_0 = \frac{E_0}{c} \) \( B_0 = \frac{30 \text{ V/m}}{3 \times 10^8 \text{ m/s}} \) \( B_0 = 1 \times 10^{-7} \text{ T} \)
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