A certain brand of freezer is advertised to use 730 kW•h of energy per year. (a) Assuming the freezer operates for 5 hours each day, how much power does it require while operating?

Verified step by step guidance

1. Calculate the total number of hours the freezer operates in a year by multiplying the number of hours per day it operates by the number of days in a year: 5 hours/day \(\times\) 365 days/year.
2. Convert the annual energy usage from kilowatt-hours to watt-hours by multiplying by 1000, since 1 kW•h = 1000 W•h.
3. Calculate the power required by the freezer while operating by dividing the total annual energy usage in watt-hours by the total number of operating hours per year. Use the formula: Power (W) = Total Energy (W•h) / Total Time (h).
4. Convert the power from watts to kilowatts by dividing by 1000, since 1 kW = 1000 W.
5. The result from the previous step gives the power in kilowatts that the freezer requires while it is operating.

Key Concepts

Power

Power is the rate at which energy is transferred or converted. It is measured in watts (W), where 1 watt equals 1 joule per second. In this context, power can be calculated by dividing the total energy consumed over a period by the time during which the energy is used.

Energy Consumption

Energy consumption refers to the total amount of energy used by an appliance over a specific time frame, typically measured in kilowatt-hours (kW•h). This measurement indicates how much energy the freezer uses in a year, which can be converted to a daily or hourly rate to find the power requirement.

Time Conversion

Time conversion is the process of changing units of time to facilitate calculations. In this problem, the annual energy consumption needs to be converted into a daily or hourly basis to determine the power requirement of the freezer. Understanding how to manipulate these time units is essential for accurate calculations.