Microwave ovens and the microwaves in our surroundings operate differently, which is why we don't feel heated by the microwaves in our environment. Here's a brief explanation:
Microwave ovens: Microwave ovens generate microwaves using a device called a magnetron. These microwaves are directed into the oven's cooking chamber, where they interact with water molecules in the food. The microwaves cause the water molecules to vibrate rapidly, generating heat through friction and effectively heating the food.
Microwaves in our surroundings: The microwaves present in our surroundings, such as those used for communication (e.g., Wi-Fi, cell phones) or radar systems, operate at different frequencies and power levels compared to microwave ovens. These microwaves are designed to be safe for human exposure and are regulated by strict international guidelines to prevent harm.
Microwave ovens are specifically designed to contain the microwaves within the cooking chamber, preventing them from escaping and potentially causing harm to people. The oven's metal casing and the mesh screen on the door reflect and contain the microwaves, ensuring they are absorbed by the food and not directed towards the user.
Additionally, our bodies are not highly sensitive to the frequencies used in microwave ovens, and the amount of microwave radiation that might leak from a properly functioning microwave is minimal and considered safe. However, it's essential to ensure that microwave ovens are in good working condition, with intact seals and no damage to the door or safety features, to maintain their safety.
In summary, microwave ovens are designed to safely contain and direct microwaves to heat food, while the microwaves present in our environment are generally at different frequencies and power levels and are not focused on heating objects like our bodies.