A microwave oven does not act as a Faraday cage to intercept radio waves and divert them to the ground. In fact, a Faraday cage is designed to block external electromagnetic fields from entering its enclosed space, while a microwave oven is designed to contain and direct microwave radiation inside its cooking chamber.
A Faraday cage is a metallic enclosure that effectively shields its interior from external electromagnetic radiation by redistributing the electromagnetic fields on its outer surface. This property is achieved because the electric charges in the conductive material rearrange themselves in response to the external fields, creating opposing electric fields that cancel out the incoming electromagnetic waves.
On the other hand, a microwave oven uses a magnetron to generate microwave radiation within the oven's cooking chamber. The walls of the microwave oven are made of conductive metal, but they are designed to keep the microwaves inside the chamber rather than reflecting them out. The holes or perforations in the metal screen of the oven door are designed to be smaller than the wavelength of the microwaves, which prevents them from escaping while allowing visible light to pass through.
When you operate a microwave oven, the generated microwaves stay confined within the cooking chamber and interact with the water molecules and other polar molecules in the food, causing them to vibrate and generate heat. The mesh of the oven door is designed to block the microwave radiation from escaping, ensuring that it remains safely contained inside the oven while cooking.
In summary, a Faraday cage is used to block external electromagnetic radiation from entering an enclosed space, while a microwave oven is designed to keep microwave radiation contained within its cooking chamber for cooking purposes.