The efficiency of a light source is the percentage of its energy input that gets radiated as visible light. If some of the blue light in an LED is used to cause a fluorescent material to glow,A. The overall efficiency of the LED is increased.B. The overall efficiency of the LED does not change.C. The overall efficiency of the LED decreases.

The efficiency of a light source is the percentage of its energy input that gets radiated as visible light. If some of the blue light in an LED is used to cause a fluorescent material to glow,A. The overall efficiency of the LED is increased.B. The overall efficiency of the LED does not change.C. The overall efficiency of the LED decreases.

College Physics

1st Edition

ISBN:9781938168000

Author:Paul Peter Urone, Roger Hinrichs

Publisher:Paul Peter Urone, Roger Hinrichs

Chapter29: Introduction To Quantum Physics

Section: Chapter Questions

Problem 15CQ: Your pupils dilate when visible light intensity is reduced. Does wearing sunglasses that lack UV...

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