Final answer:
A common microwave oven draws about 1,500 watts of power but realistically uses around 700 watts. The actual energy consumption depends on how long it is used, with a typical usage of 12 minutes a day translating to 0.14 kWh per day.
Step-by-step explanation:
A common microwave oven typically draws about 1,500 watts (W) of electrical power. However, not all of this power is used to heat the food. For a realistic estimation, it is better to consider that approximately 700 W is effectively used. The actual energy usage of a microwave will depend on its usage or duty cycle, which describes how often it is on.
For instance, if a microwave is used for about 12 minutes a day, or 0.2 hours, at 700 W, then it would consume 0.14 kilowatt-hours (kWh) of energy per day. In comparison, a 25 W television tuner box that runs continuously (24 hours a day) would use 0.6 kWh in a day. Hence, even though both devices might have the same power rating, the actual energy consumption depends on operational time.