Choose the false statementa)For pure metal thermal conductivity is mor...
Thermal conductivity increase with increase in density of substance.
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Choose the false statementa)For pure metal thermal conductivity is mor...
Thermal Conductivity and Density
Thermal conductivity is the ability of a material to conduct heat. It is measured in units of W/mK. The higher the thermal conductivity, the better the material is at conducting heat. Density, on the other hand, is the measure of mass per unit volume. The relationship between thermal conductivity and density is as follows:
- For pure metal thermal conductivity is more: This statement is true. Pure metals are excellent conductors of heat due to their high thermal conductivity. This is because the atoms in metals are closely packed, allowing heat to be transferred quickly through the material.
- Thermal conductivity decreases with increase in the density of the substance: This statement is false. The thermal conductivity of a substance is not directly related to its density. For example, diamond is one of the densest materials known, but it also has an extremely high thermal conductivity.
- Thermal conductivity of dry material is lower than that of damp material: This statement is true. Damp materials, such as wet soil or wet wood, have a higher thermal conductivity than dry materials. This is because water is a good conductor of heat, so it helps to transfer heat through the material more efficiently.
- Heat treatment causes variation in thermal conductivity: This statement is true. Heat treatment can cause changes in the microstructure of a material, which can affect its thermal conductivity. For example, annealing can increase the thermal conductivity of metals by reducing the number of defects in the crystal structure.
In summary, the statement that "thermal conductivity decreases with increase in the density of the substance" is false. The thermal conductivity of a substance depends on a variety of factors, including its crystal structure, composition, and temperature.