Heat and Thermal Energy – Particle Movement)

Everything around you is made of tiny particles that are constantly jiggling and vibrating, from a hot iron to a snow-covered house. The energy of these moving particles is called thermal energy. The faster the particles move, the more thermal energy something has, and the hotter it feels. Let's say, for example, we have three beakers containing the same amount of water. One with cold water, one with warm water, and one with hot water. Particles move slowly in cold water, faster in warm water, and even faster in hot water. Let's look at another example. In solid ice, the particles are locked in place in a rigid arrangement, vibrating, but not free to move about. When the ice cube is heated in a petri dish, the particles vibrate faster and faster. Eventually, they're moving so much that they break free from their rigid structure and start sliding past each other. The ice has melted into liquid water. As the heating continues, the particles move even faster, until they're bouncing around so vigorously that they escape from the liquid entirely, bubbling up as steam and rising into the air as water vapor. But here's where things get interesting. Thermal energy doesn't stay put. It's constantly moving between objects, always traveling from hotter things to cooler things. Think about a metal spoon sitting in a mug of hot chocolate. The thermal energy in the hot drink doesn't just sit there. It moves into the cooler spoon, heating it up while the drink gradually cools down. This continues until the spoon and the drink reach the same temperature. We call this movement of thermal energy heat. And heat has three clever ways of getting around. Conduction, convection, and radiation. Want to see how each one works? Check out the related videos.