Find solution
Which do compact fluorescent bulbs have the shortest warm-up period?

Calculating kilowatt hrs of power in a 30-day period???? Help?

  • A home owner finds that she has a total of 42 light bulbs (100W) in use in her home. 1. if all of the bulbs are on for an average of 5 h per day, how many kilowatt hours of electricity will be consumed in a 30-day period? 2. At 11 cents per kilowatt hour, how much will operating these lights cost the home owner during that period? Please help on determining how to calculate. I would be able to calculate it right away but I don't have a formula, and it wasn't thorough when my teacher explained. If any of you who has knowledge of it please help me figure the formula? 5 Stars! thank you in advance

  • Answer:

    The total power consumption of 42 light bulbs each of 100 W is just = 42 * 100 W = 4200 W There are 1000 W in 1kW, so the power consumption can also be written as 4.2 kW If the lights are on for 5h each day, that will consume 5h * 4.2kW = 21 kWh per day. So in 30 days, that is a total energy of (30 * 21) = 630 kWh At 11 cents/ kWh that comes to 630 kWh * 11 c/kWh = 6930 cents or $69.30

darkrai at Yahoo! Answers Visit the source

Was this solution helpful to you?

Other answers

42 bulbs x 100W each = 4200W = 4.2 kW (kilowatt) 4.2kW * 5 hours/day = 21 kWh/day (kilowatt hours/day) 21 kWh/day x 30 days = 630 kWh 630 kWh x $0.11/kWh = $69.3

Taylor

42 bulbs x 100W each = 4200W = 4.2 kW (kilowatt) 4.2kW * 5 hours/day = 21 kWh/day (kilowatt hours/day) 21 kWh/day x 30 days = 630 kWh 630 kWh x $0.11/kWh = $69.3

The total power consumption of 42 light bulbs each of 100 W is just = 42 * 100 W = 4200 W There are 1000 W in 1kW, so the power consumption can also be written as 4.2 kW If the lights are on for 5h each day, that will consume 5h * 4.2kW = 21 kWh per day. So in 30 days, that is a total energy of (30 * 21) = 630 kWh At 11 cents/ kWh that comes to 630 kWh * 11 c/kWh = 6930 cents or $69.30

lunchtim...

Energy per day = 42*100*5=21000 Watt-hours or 21 KW-hr thus in 30 days = 21*30=630 KW-hr At $0.11 per KW-h the cost is 0.11*630=$69.3

GRAHAM

Energy per day = 42*100*5=21000 Watt-hours or 21 KW-hr thus in 30 days = 21*30=630 KW-hr At $0.11 per KW-h the cost is 0.11*630=$69.3

GRAHAM

Related Q & A:

Just Added Q & A:

Find solution

For every problem there is a solution! Proved by Solucija.

  • Got an issue and looking for advice?

  • Ask Solucija to search every corner of the Web for help.

  • Get workable solutions and helpful tips in a moment.

Just ask Solucija about an issue you face and immediately get a list of ready solutions, answers and tips from other Internet users. We always provide the most suitable and complete answer to your question at the top, along with a few good alternatives below.