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Conduction is the transfer of heat through direct contact. When a hot object touches a cooler one, the fast-moving particles in the hot object bump into the slower particles in the cool object, passing along their energy. Metals are excellent heat conductors — that is why a metal spoon in hot soup gets hot quickly. Materials like wood, plastic, and cloth are poor conductors of heat, which is why pot handles are often made of those materials.
Place a metal spoon, a wooden spoon, and a plastic spoon in a cup of hot water. After a minute, feel the handles to compare how much heat each conducted. Stick butter pats to different material rods placed in hot water and see which one melts the butter first. Discuss why oven mitts work.
Touch a metal railing on a cold day and it feels freezing. Touch a wooden fence right next to it and it feels much warmer. But both objects are the same temperature — so why do they feel different? The answer is conduction. Metal is an excellent conductor of heat, so it quickly pulls heat away from your warm hand, making it feel cold. Wood is a poor conductor, so it transfers heat from your hand much more slowly, and it does not feel as cold.
Conduction is the transfer of heat through direct contact between particles. Here is how it works at the particle level: when a hot object touches a cooler one, the fast-moving particles in the hot object crash into the slower particles in the cool object. Each collision passes some energy along, and gradually the cooler object warms up while the hotter object cools down. This process continues until both objects reach the same temperature.
Not all materials conduct heat equally. Metals like copper, aluminum, and iron are excellent conductors because their particles are tightly packed and have free-moving electrons that carry energy quickly. That is why pots and pans are made of metal — you want the heat from the stove to move efficiently into the food. Non-metals like wood, plastic, rubber, and cloth are poor heat conductors. Their particles do not pass energy along nearly as well, which makes them useful for handles, gloves, and insulation.
Conduction is one of three ways heat can transfer (the other two are convection and radiation). It happens anytime two objects at different temperatures touch. When you sit on a cold bench, heat from your body conducts into the bench. When you pick up a warm cup, heat conducts from the cup into your hand. Even the floor under your feet is involved — a tile floor feels colder than a carpeted floor because tile conducts heat away from your feet much faster. Understanding conduction helps explain why we choose certain materials for cooking, building, and staying comfortable.