Answer / karthik

for single phase, P=VIcos0.
When P=100W, Icos0=P/V.
Icos0=100/230.
for 100 nos, Icos0=100*100/230
=43.48A
if cos0=0.9, I=48.3A

Answer / errol

assuming a 230V power supply:
I=P/V where P= 100W x 100pcs = 10,000watts
Total current, I, therefore is 10,000W/230V = 43.48A. The power factor is 100% bearing in mind that bulbs are resistive loads.

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