An air conditioner has a power rating of 3500 \(\rm{W}\). How much energy is use for 12 hours?
Answer
\(42~\rm{kWh}\)
Worked Solution
Question 2
11363
A clothes dryer has a power rating of 3000\(W\). If the cost of electricity is 24 cents per kilowatt - hour and the cost of operating the dryer was $87.84, then the number of hours that the dryer was used was?
Answer
\(122\)
Worked Solution
Question 3
11361
Sally uses a 1800\(W\) heater for 4 hours a day. How much energy does it use in 2 weeks?
Answer
\(\text{100.8 kW}\)
Worked Solution
Question 4
11362
An energy company charges for gas over a 3 month period of $0.02560 per MJ. The charge for 3200MJ would be?
Answer
\(\$ 81.92\)
Worked Solution
Question 5
10323
Marry uses a 10\(~\rm{W}\) laptop for a total of 5 hours each day.
She is charged at a rate of 24.05 cents per kilowatt-hour.
What is the cost of running the laptop for a year?
Answer
\(\$ 4.39\)
Worked Solution
Question 6
10334
Fred uses a 12\(~\rm{W}\) fan for 10 hours of a day. How much energy does the fan use for a week?
Answer
\[0.84~\rm{kWh}\]
Worked Solution
Question 7
10317
Tom uses an oven with a rating of 1400\(~\rm{W}\) for an average of 8 hours per week.
The cost of electricity for a week at 22.31 cents per kilowatt - hour is?
Answer
\(\$ 2.50\)
Worked Solution
Question 8
10336
How many hours was a clothes washer used with a power rating of 1200\(W\), if the cost of operating it was $ 36.
Given that the cost of electricity is 25 cents per kilowatt-hour.
Answer
\(\text{120 hours}\)
Worked Solution
Question 9
10511
An energy company charges for gas over a 3 month period at $0.02890 per\(\text{ MJ.}\) Angus recieved a bill for $130.05. The amount of gas used was?
Answer
\(\text{4500 MJ}\)
Worked Solution
Question 10
119249
Sally uses a \(25\)W ceiling fan for 8 hours of the day. What is the cost of using the ceiling fan for a week if the electricity is \(\$ 0.45\) per kWh?
