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Question
Temperature dependence of resistivity ρ(T) of semiconductors, insulators and metals is significantly based on the following factors:
- number of charge carriers can change with temperature T.
- time interval between two successive collisions can depend on T.
- length of material can be a function of T.
- mass of carriers is a function of T.
Options
a and b
b and c
c and d
a and c
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Solution
a and b
Explanation:
Resistivity is the intrinsic property of the substance. For a metallic conductor, resistivity is given by
`ρ = m/("ne"^2τ)`
Where n is the number of charge carriers per unit volume (number density) which can charge with temperature T and τ is relaxation time (time interval between two successive collisions) which decreases with the increase of temperature `(T oo 1/τ)`.
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