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There has to be a vast difference because when my cast iron stove is cold, it takes a long time to warm up. If it is even slightly warm from a previous fire it heats very quickly. The question I suppose I should be asking is how does heat as a form of radiation move through solid objects. Like the sun? Protons and neutrons bouncing around forever before they reach the surface?

2007-02-19 16:37:13 · 2 answers · asked by brokolay 3 in Science & Mathematics Physics

2 answers

The reason a cast ion stove takes a long time to warm up is not that it is a poor conductor of heat, but because it has a very high density compared to air, that is has a lot of mass, so it takes a lot of heat to make it hot.
Metals are very good conductors of heat because their electrons are free to move and take thermal energy with them as they move. Solids that have bound electrons and are poor conductors of electricity are usually poor heat conductors, but there are exceptions. Diamond is the best conductor of all solids.
In fluids (gases and liquids) heat transfer takes place through convection, the movement of atoms and molecules. The sun is a plasma ( a gas that is so hot that the electrons are freed from atoms by thermal collisions) and since at the velocity of an electrons is greater than protons and neutrons because they have less mass, the conduction of heat in the sun is mostly due to the movement of electrons and radiation. Radiation is usually not important unless the temperature is very high.

2007-02-20 00:46:08 · answer #1 · answered by meg 7 · 0 0

Heat is spread in 3 ways: conduction, convection and radiation. Heat is also thought to be the random vibration of molecules of a substance. Conduction occurs when vibrating molecules jostle surrounding molecules and cause them to vibrate too. This spreads through the material. Convection occurs when a warmer region moves through the substance, because it's less dense. This only occurs in liquids and gases. Radiation involves electromagnetic radiation, and is the only means to transmit heat through a vacuum. So, metals only spread heat by conduction whereas air and water can spread heat through all 3 materials.
Free protons and neutrons are very rare, they're usually confined to the nuclei of atoms.

2007-02-20 03:01:53 · answer #2 · answered by AaronX 2 · 0 0

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