A filament lamp-
cost- 80p
effiency- 0.2
expected life- 1000 hours
a compact fluorescent lamp (CFL)-
cost- £3.00
effiency- 0.8
expected life- 8000 hours
a filament lamp with a power rating of 100W gives 2000 units of light.
what power rating would a CFL need to provide 2000 units of light?
a)8000W
b)20W
c)25W
d025W
3 answers