Factors affecting thermal conduction in solids
i)Temperature difference between the ends of the material
More heat flows when the temperature difference is large.
ii)cross-section area
The thermal conductivity of a thicker material is higher than that of a thinner one of the same material. This is because the number of free electrons (metals only) per unit length of the thicker material is higher than that of a thinner one. Also, the number of atoms vibrating per unit length of the thicker material is higher than that of a thinner one.
iv)Length of the conductor
Heat energy reaches the other end of a shorter conductor faster than a longer one. Heat travels in a conductor along imaginary lines known as lines of heat flow. These lines diverge away from the hot end and therefore as the length of the conductor increases
v)Nature of the material
Some materials are good conductors while others are bad conductors e.g. copper is a better conductor compared to iron.
The rate of conduction depends on:
1. Amount of temperature – the higher the temperature the higher the rate of transfer.
2. Cross-sectional area – the larger the cross-sectional area the higher the transfer.
3. Length of material – the shorter the material the higher the rate of transfer.
4. Type of material – different materials transfer heat at different rates.
Moraa orina answered the question on April 6, 2018 at 17:58
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