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An electric bulb is rated as 200 W. What will be the peak magnetic field at 4 m distance produced by the radiations coming from this bulb? Consider this bulb as a point source with 3.5% efficiency.

1. 1.19 × 10 –8 T
2. 1.71 × 10 –8 T
3. 0.84 × 10 –8 T
4. 3.36 × 10 –8 T

Correct answer: 1.71 × 10 –8 T

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