How can you test a microwave oven to ensure it is operating correctly?

To test a microwave oven for correct operation, using a cup of water is an effective method. When you place a cup of water inside the microwave and set it to run for a specific duration, you can assess whether the microwave heats the water adequately. Microwaves work by agitating water molecules, leading to heating; therefore, if the water becomes warm or hot after the prescribed cooking time, this indicates that the microwave is functioning properly.

Observing the timer can confirm that the microwave is capable of tracking time, but it does not provide direct evidence of heating capability. Using a thermometer, while it can measure the temperature of the water, is often unnecessary for a basic functionality test and might not be as straightforward as simply checking the heat of the water itself. Checking the power cord is important for ensuring that the microwave has an electrical supply, but it does not test the actual heating performance of the appliance.