A heater uses 20 A when used in a 110-V line. If electric power costs 10 cents per kilowatt hour, the cost of operating the heater for 10 hours is
A)$0.22.
B)$0.55.
C)$2.20.
D)$5.50.
E)none of the above

Question

Quizplus · Accepted Answer

We can start by using the formula:

Power (in watts) = Current (in amperes) x Voltage (in volts)

So, the power of the heater is:

Power = 20 A x 110 V = 2200 W

Next, we need to find the total amount of energy used in 10 hours. We can use the formula:

Energy (in kilowatt-hours) = Power (in kilowatts) x Time (in hours)

We know the power in watts, so we need to convert it to kilowatts:

Power = 2200 W = 2.2 kW

Now we can find the energy used:

Energy = 2.2 kW x 10 hours = 22 kWh

Finally, we can calculate the cost:

Cost = Energy x Cost per kWh

Cost = 22 kWh x $0.10/kWh = $2.20

So, the cost of operating the heater for 10 hours is $2.20, which is answer choice (C).

A Heater Uses 20 a When Used in a 110-V