Fluorescent bulbs have recently become much more efficient due to the introduction of

A) high-emission phosphor coatings on the inside of the bulb.
B) new types of gases, that glow brighter, within the tube.
C) lower density--i.e., lower pressure--gases within the tube.
D) electronically controlled high-frequency ballasts.
E) longer bulbs.


D

Physics & Space Science

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Physics & Space Science