4. Assume that half of the light emitted by a 100 W incandescent lamp (1750 lumens) illuminates a 100 ft2 surface. a. Determine the average illuminance of the surface in foot-candles. b. Determine the average illuminance of the surface in lux. c. What would the average illuminance be if only half of the light illuminated the surface?

4. Assume that half of the light emitted by a 100 W incandescent lamp (1750 lumens) illuminates a 100 ft2 surface. a. Determine the average illuminance of the surface in foot-candles. b. Determine the average illuminance of the surface in lux. c. What would the average illuminance be if only half of the light illuminated the surface?

Engineering Fundamentals: An Introduction to Engineering (MindTap Course List)

5th Edition

ISBN:9781305084766

Author:Saeed Moaveni

Publisher:Saeed Moaveni

Chapter11: Temperature And Temperature- Related Variables In Engineering

Section: Chapter Questions

Problem 8P

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