Microwave Oven Mystery: Why Does a Plastic or Glass Dish Stay Cool After Microwaving?

Have you ever noticed that an empty plastic or glass dish is cool to the touch after being removed from a microwave oven? How is this possible?

1. Plastic and glass are both poor heat conductors. They are insulators which means their electrons don’t move as freely as conductors.

Explanation:

When you microwave food in a plastic or glass dish, the dish itself does not absorb much heat from the microwave radiation. This is because plastic and glass are both poor heat conductors, also known as insulators. Insulators do not allow heat to pass through them easily because their electrons do not move as freely as conductors like metal.

Plastic and glass dishes are designed to heat food evenly without becoming hot themselves. The microwave radiation excites the water molecules in the food, causing them to vibrate and generate heat. Since plastic and glass do not absorb much of this radiation, they remain relatively cool to the touch even after microwaving. This phenomenon is similar to how you can touch a wooden spoon in a pot of boiling water without getting burned, as wood is also a poor conductor of heat.

It's important to note that while the dish itself may feel cool, the food inside can still be very hot. Always use caution when handling microwaved food to avoid burns. Additionally, make sure to use microwave-safe dishes to prevent any melting or leaching of chemicals into your food.

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