2006-10-08 02:02:29 · 6 answers · asked by macky 1 in Science & Mathematics ➔ Engineering
this is the formulae for calculating electrical consumption
(energy used=kilowatt x hour)
-thus, 9 watt is changed into kilowatt=
0.009kw
-then,0.009 x 8 hours=0.072 kwh
-since the bulb is used for 30 days, then 0.072 x 30days=2.16 kwh
answer: 2.16 kwh
2006-10-08 02:13:33 · answer #1 · answered by ananya 1 · 0⤊ 0⤋
Continuing from Prof. Science's good answer:
2160 Watt-hours x (0.001 kiloWatt / Watt)
= 2.16 kiloWatt-hours.
At a typical rate of 10-to-15 cents per kW-hr, it would cost only about 20 to 30 cents per month to run that bulb.
2006-10-08 02:16:40 · answer #2 · answered by genericman1998 5 · 0⤊ 0⤋
9W x 8 hours x 30 days = 2160 Watt hours
2006-10-08 02:04:59 · answer #3 · answered by Anonymous · 0⤊ 0⤋
9W * 8 hrs * 30 days = 2160 Watt-hrs
1kW-hr is typically ~10-15 cents in the US.
2006-10-08 14:43:31 · answer #4 · answered by ee 2 · 0⤊ 0⤋
9x8x30= 2160 watts, or 2.16 kilowatts
2006-10-08 03:22:38 · answer #5 · answered by Max 6 · 0⤊ 0⤋
What the professor said.
2006-10-08 02:05:39 · answer #6 · answered by Obsean 5 · 0⤊ 0⤋