Find an electrical appliance or device in your home that is used by you or your family regularly. Calculate the cost to use this device continuously for one hour, and one day (24 hours). Estimate the percentage of time the device is actually used and calculate how much it normally costs you to use the device for one week and for the whole year. (4 calculations in all)
To calculate energy use, you must know the power rating of the device. This is often marked on a label near where the plug connects to the device. You may have to calculate the power if the current rating is marked instead of the power. The power companies use the unit of kilowatt-hours for energy, so we must convert the power to kilowatts and multiply by the time the appliance is used in hours to get the energy in kilowatt-hours. To calculate the expense, you must find out how much electricity costs you. Find an old electric bill and divide the cost of energy used by the number of kilowatt-hours used to get the cost per kilowatt-hour. Now you can calculate the cost of using your device.
Write a summary of your investigation. Include all data recorded for the appliance, data from your electric bill that you used to calculate your electricity cost per kilowatt-hour, and calculations you made to find the four costs for using the appliance. Discuss any alternatives to using these appliances or adjustments that you could make in order to conserve electric energy and save money.
This assignment will replace one daily grade.
E = P/t P = VI