A 200 W sodium street lamp emits yellow light of wavelength 0.6 µm. Assuming it to be 25%…
Physics · JEE Main · NTA Exams — Atoms and Nuclei
A 200 W sodium street lamp emits yellow light of wavelength 0.6 µm. Assuming it to be 25% efficient in converting electrical energy to light, the number of photons of yellow light it emits per second is
- 3 × 1019
- 1.5 × 1020
- 6 × 1018
- 62 × 1020
Answer
(B) 1.5 × 10 20
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