TS EAMCET · Physics · Electromagnetic Waves
A electric bulb produces electromagnetic radiation with electric field amplitude of at a distance of . Assuming it as a point source, estimate the efficiency of the bulb.
- A
- B
- C
- D
Answer & Solution
Correct Answer
(C)
Step-by-step Solution
Detailed explanation
Intensity =power×ηA ...1 We know, 12I=12ε0E2c I=8.854×10-12223×108 I=0.0106 w m-2 ...2 On substituting 2 in 1, 0.0106=100×η4×π×102…
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