When you turn on a microwave oven, it generates electromagnetic waves called microwaves. These microwaves are directed into the cooking chamber and interact with the food, causing various effects that lead to the heating and cooking of the food. Here's what happens when microwaves are turned on inside a microwave oven:
Absorption of Microwaves: Microwaves are absorbed by water, fats, and certain other molecules present in the food. Water molecules are particularly effective at absorbing microwaves, and most foods contain at least some water content. As the microwaves penetrate the food, they interact with these molecules, causing them to vibrate rapidly.
Vibration and Friction: The rapid vibration of water molecules causes friction between neighboring molecules. This friction generates heat throughout the food, leading to a uniform and rapid increase in temperature.
Transfer of Heat: Unlike traditional ovens, which heat food from the outside in, microwaves cook food from the inside out. The heat generated within the food is conducted to the colder parts, ensuring more efficient cooking in a shorter time.
Steam Generation: As water molecules absorb microwaves and heat up, they can turn into steam. This steam helps keep the food moist and contributes to the cooking process.
Effect on Non-Polar Molecules: Microwaves do not have a significant effect on non-polar molecules like oils and fats. Consequently, these substances might not heat up as quickly as water-containing parts of the food.
Microwaves Penetration: Microwaves can penetrate a few centimeters into the food, depending on the frequency and power of the microwave oven. Thicker foods might require longer cooking times to ensure that the microwaves reach the center and cook the food evenly.
It's important to follow the microwave cooking instructions and use appropriate containers to ensure safe and efficient cooking. Microwaves are specifically designed to interact with water molecules, which is why certain materials, such as metal or aluminum foil, should never be used inside microwave ovens, as they can cause sparks and potential fire hazards. Always use microwave-safe cookware and follow the manufacturer's guidelines to achieve the best cooking results while maintaining safety.