GyanGramEnvironment · Prelims 2011 Q804
What is the difference between a CFL and an LED lamp? 1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semiconductor material. 2. The average lif…
Stem and options.
What is the difference between a CFL and an LED lamp?
1. To produce light, a CFL uses mercury vapour and phosphor while an LED lamp uses semiconductor material.
2. The average lifespan of a CFL is much longer than that of an LED lamp.
3. A CFL is less energy-efficient as compared to an LED lamp.
Which of the statements given above is/are correct?
Source: UPSC Civil Services Preliminary Examination 2011. Syllabus tags and explanation are GyanGram editorial joins for learning—not official UPSC metadata.
Correct option C
• Correct Answer: C
• CFL uses mercury vapour and phosphor; LED uses semiconductor material (electroluminescence).
• LED lifespan (25,000–50,000 hours) exceeds CFL (~8,000–10,000 hours); CFL wastes ~80% energy as heat.
Where this sits in Learn.
Unit
Clean Energy
ENV-U09Chapter
Energy Transition
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