Question

The average rated life of a lamp refers to the point where 50 percent of a test batch of lamps are still operating. The "lamp life" of an incandescent lamp is 750 to 1000 hours. How much greater is the lamp life of a halogen lamp? A 9-watt compact fluorescent has a lamp life of 10,000 hours. Is the lamp life of an 18-watt fluorescent greater or less?

Answer

Halogen lamp life is about twice that of incandescent, about 2000 hours. An 18-watt fluorescent has a 2000-hour-longer lamp life than a 9-watt fluorescent.