A football pitch 120m x 40 m is to be illuminated for night play by similar banks of equal 1500W lamps supported on twelve towers which are distributed around the ground to provide approximately uniform illumination of the pitch. Assuming that 38% of the total light emitted reaches the playing pitch and that an illumination of 900 lux is necessary for television purposes, calculate the number of lamps on each tower. The overall efficiency of the lamp is to be taken as 31 lm/W. The maintenance factor is 0.99. Give the computed numerical value in your answer not the rounded-off integer number of lamps.

A football pitch 120m x 40 m is to be illuminated for night play by similar banks of equal 1500W lamps supported on twelve towers which are distributed around the ground to provide approximately uniform illumination of the pitch. Assuming that 38% of the total light emitted reaches the playing pitch and that an illumination of 900 lux is necessary for television purposes, calculate the number of lamps on each tower. The overall efficiency of the lamp is to be taken as 31 lm/W. The maintenance factor is 0.99. Give the computed numerical value in your answer not the rounded-off integer number of lamps.

EBK ELECTRICAL WIRING RESIDENTIAL

19th Edition

ISBN:9781337516549

Author:Simmons

Publisher:Simmons

Chapter33: Residential Utility-interactive Photovoltaic Systems

Section: Chapter Questions

Problem 1R

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