" 3.(i) Define the term drift velocity."

Answer the following: (i) Define the term drift velocity . (ii) On the basis of electron drift , derive an expression for resistivity of a conductor in terms of number density of free electrons and relaxation time. On what factors does resistivity of a coductor depend ? (iii) Why alloys like constantan and manganin are used for making standard restores ?

Define drift velocity.

Define drift velocity.

(i) Define the term drift velocity . (ii) On the basis of electron drift , derive an expression for resistivity of a conductor in terms of number density of free electrons and relaxation time. On what factors does resistivity of a coductor depend ? (iii) Why alloys like constantan and manganin are used for making standard restores ?

Define the terms. Velocity.

Define the term 'drift velociy' and 'relaxation time' giving their physical significance.

Define genetic drift?

Define genetic drift?