Light emitting diodes (LEDs) are preferred over incandescent bulbs primarily because: MCQ with Answer and Explanation

Light emitting diodes (LEDs) are preferred over incandescent bulbs primarily because:
A. They emit a wider spectrum of light.
B. They consume more power but last longer.
C. They are highly energy-efficient and convert most energy into light.
D. They rely on a heated filament.
Answer: Option C
Solution (By JKExamLibrary)
Incandescent bulbs work by heating a tungsten filament until it glows, converting roughly 90% of electrical energy into wasted heat and only 10% into light. LEDs are solid-state semiconductors that emit light through electroluminescence. They convert almost all their electrical energy directly into light, making them significantly more efficient and cooler.

This question belongs to: Science Physics

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Correct Answer: Option B


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Correct Answer: Option D


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This question belongs to: Science Physics