Question

Two conductors of same material having equal lengths but radii in the ratio 1:3 are connected in series across a battery. The drift velocity of the free electrons through them will be in the ratio of

Answer 1

9:1

Explanation:

The expression for drift velocity is given by=

Vd= I/neA,

where, I is the current flowing through the conductor,

n is the number of electrons

e is the charge of electron

and A is the area of conductor.

Let the give materials be A and B,

Given- rA:rB= 1:3

Vd=I/neA

    =I/neπ$r^{2}$

(Vd)A:(Vd)B= $(r)B^{2}$ /$rA^{2}$

=(3)^2/1^2

=9:1