Question

Electric power costs 17.8 cents per kWh in Los Angeles in July 2017 (compared to the national average of 14.3 cents per kWh). How much did it cost (in cents) to run a 1500 W hair dryer for 10 minutes in Los Angeles during July 2017? Assume 3 significant digits in your answer.

Answer 1

The cost to run a 1500 W hair dryer for 10 minutes in Los Angeles during July 2017 is:

4.45 cents

Explanation:

Electric power costs 17.8 cents per kWh in Los Angeles in July 2017.

Now we are asked to find the cost to run a 1500 W hair dryer for 10 minutes in Los Angeles during July 2017.

We know that: 1 w=0.001 kW

This means that:

1500 W= 1.500 kW

Also, it is used for 10 minutes

i.e. 1/6 hours

Hence, the electric power used to run the hair dryer is: 1.500×(1/6)

i.e. Electric power to used by hair dryer is: 0.25 kWh

Cost of 1 kwh is: 17.8 cents

This means that cost of 0.25 kwh is: 17.8×0.25

= 4.45 cents

Hence, the answer is:

4.45 cents