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.

Introductory Circuit Analysis (13th Edition)

13th Edition

ISBN:9780133923605

Author:Robert L. Boylestad

Publisher:Robert L. Boylestad

Chapter1: Introduction

Section: Chapter Questions

Problem 1P: Visit your local library (at school or home) and describe the extent to which it provides literature...

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