Final answer:
The rating label on an appliance shows the voltage, frequency, and watts the appliance consumes. A toaster has a higher wattage than a digital clock due to its greater energy need for heating. Estimating energy consumption involves multiplying power rating by usage time, and can help manage electrical costs.
Step-by-step explanation:
The voltage, frequency, and watts an appliance consumes are indicated on the appliance's rating label. This label is crucial as it informs you about the electrical requirements and power consumption of the appliance. For instance, a toaster tends to have a higher power rating than a digital clock because it requires more electrical energy to generate heat to toast bread.
To estimate the energy consumed by appliances in an average day, you can multiply their power rating by the time they're in use. For instance, if you use a 1200-watt toaster for 5 minutes daily, it would consume 0.1 kilowatt-hours of energy per day. If some appliances state only the operating current, use the formula P = IV (power equals current times voltage) assuming a household voltage of 120 V.
Understanding power consumption helps manage electrical costs. For example, if fluorescent lights rated at 32 W were inadvertently left on over the weekend at a school, you could calculate the cost by multiplying the total hours by the power rating and then by the cost of electricity per kilowatt-hour.