1A)
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
1B)
elecricity costs 15p per KWh.
what will be the cost of using a 100W filament lamp during it's expected life?
a)£1.50
b)£15.00
c)£150.00
d)£1500.00
1C)
in it's lifetime, a security light is used for 15000 hours.
how much would you expect to spend on buying CFLs for the security light in that time?
a)£5.63
b)6.00
c)12.00
d)£45.00