when an object attached to other objects, the temperature will rise in this place. The molecules vibrated faster even though stay in place, the molecules that transmit the vibrations to the surroundings. That's how the heat propagates through conduction.
All objects conduct heat, some things are much more effective than others. Copper, for example, is a special conductor, while the glass is not, if the pencil-thin copper rod is held with one end in the fire, the other end will soon be too hot to hold. Heat has been propagated from the hot end to the other. When a glass with the same size held in a fire in the same way, the heat will run along the rod was very slowly. We can hold the ends are not heated by hand although the other end is very hot. Very poor conductor, called an insulator.
solids are better conductors than liquids, and liquids are better than gas. While the solid metal in particular is a good conductor. Silver, copper, aluminum is the best of everything. Instead many solid materials such as wood, paper, and cork is a poor conductor because it has a lot of air space. Air is a good insulator.
With simple experiments we could show that a liquid such as water is a poor conductor of heat. Put a little ice to the bottom of the the tube and hold the ice under a small lead sinker or a lump of steel fibers. Fill the the tube about three-quarters of it with water and put the tube in the flame in such a way (can tilt 45 degrees) so that only the top of the water exposed to heat. Since water is a poor conductor, the ice will not melt even the water in the top of the the tube is boiling. transmit heat water only about 1/650 times compared to silver.
The air is a more effective insulator than water. Air dissipates heat 1/25 times of water. However, to isolate objects properly, air should be were maintained so as not to move. If allowed to move, air carries heat by convection. Insulating properties of objects like sawdust, wood fiber, of felt, and cork because of too many small rooms that contain air "dead" wool blankets and warm clothing to provide warmth as much air trapped between the long hairs of the fur animals. That is why feathers provide excellent protection against the cold.
All objects conduct heat, some things are much more effective than others. Copper, for example, is a special conductor, while the glass is not, if the pencil-thin copper rod is held with one end in the fire, the other end will soon be too hot to hold. Heat has been propagated from the hot end to the other. When a glass with the same size held in a fire in the same way, the heat will run along the rod was very slowly. We can hold the ends are not heated by hand although the other end is very hot. Very poor conductor, called an insulator.
solids are better conductors than liquids, and liquids are better than gas. While the solid metal in particular is a good conductor. Silver, copper, aluminum is the best of everything. Instead many solid materials such as wood, paper, and cork is a poor conductor because it has a lot of air space. Air is a good insulator.
With simple experiments we could show that a liquid such as water is a poor conductor of heat. Put a little ice to the bottom of the the tube and hold the ice under a small lead sinker or a lump of steel fibers. Fill the the tube about three-quarters of it with water and put the tube in the flame in such a way (can tilt 45 degrees) so that only the top of the water exposed to heat. Since water is a poor conductor, the ice will not melt even the water in the top of the the tube is boiling. transmit heat water only about 1/650 times compared to silver.
The air is a more effective insulator than water. Air dissipates heat 1/25 times of water. However, to isolate objects properly, air should be were maintained so as not to move. If allowed to move, air carries heat by convection. Insulating properties of objects like sawdust, wood fiber, of felt, and cork because of too many small rooms that contain air "dead" wool blankets and warm clothing to provide warmth as much air trapped between the long hairs of the fur animals. That is why feathers provide excellent protection against the cold.
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