Question

What is the cost of operating a 3.00-W electric clock for a year if the cost of electricity is $0.0900 per kW·h?

a) $79.15
b) $87.60
c) $94.20
d) $102.75

Answer 1

To calculate the cost of operating the electric clock, multiply the energy consumed by the cost of electricity. The energy consumed can be found using the formula E = Pt, where E is the energy, P is the power, and t is the time.

Step-by-step explanation:

To calculate the cost of operating the electric clock, we need to find the energy consumed by the clock and then multiply it by the cost of electricity. The energy consumed by the clock can be calculated using the formula E = Pt, where E is the energy, P is the power, and t is the time.

In this case, the power of the clock is 3.00 W and the time is 1 year, which is equivalent to 365 days. We can convert the power to kilowatts by dividing by 1000: P = 3.00 W ÷ 1000 = 0.003 kW.

Using the formula E = Pt, we have E = 0.003 kW × 365 days = 1.095 kW·h.

Finally, we can calculate the cost of operating the clock by multiplying the energy consumed by the cost of electricity per kilowatt-hour: Cost = 1.095 kW·h × $0.0900/kW·h = $0.099.