Suppose a current-carrying wire has a cross-s | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(C) The current $I$ flowing through any cross-section of a conductor in a steady state is constant,so $I$ is the same at all points.Using the relation

Vedclass · Accepted Answer

Drift speed of electrons at point $A$ is lesser than that at point $B$.

Vedclass · Answer

(C) The current $I$ flowing through any cross-section of a conductor in a steady state is constant,so $I$ is the same at all points.Using the relation $I = neA V_d$,where $n$ is the number density of electrons,$e$ is the charge of an electron,$A$ is the cross-sectional area,and $V_d$ is the drift speed.Since $I$,$n$,and $e$ are constant,we have $V_d \propto \frac{1}{A}$.As the cross-sectional area $A$ decreases along the wire from $A$ to $B$,the drift speed $V_d$ must increase.Therefore,the drift speed at point $A$ is less than the drift speed at point $B$,i.e.,$(V_d)_A < (V_d)_B$.

Suppose a current-carrying wire has a cross-sectional area that gradually becomes smaller along the wire,having the shape of a very long cone as shown in the figure. Choose the correct statement.

Similar Questions

$A$ charged particle is moving in an electric field of $3 \times 10^{-10} \text{ Vm}^{-1}$ with mobility $2.5 \times 10^6 \text{ m}^2 \text{V}^{-1} \text{s}^{-1}$. Its drift velocity is:

Write Ohm's law in the form of current density (vector form).

$A$ steady current $I$ is set up in a wire whose cross-sectional area decreases in the direction of the flow of the current. Then,as we examine the narrowing region,

What is relaxation time?

$A$ copper wire of length $1 \,m$ and uniform cross-sectional area $5 \times 10^{-7} \,m^{2}$ carries a current of $1 \,A$. Assuming that there are $8 \times 10^{28}$ free electrons per $m^{3}$ in copper,how long will an electron take to drift from one end of the wire to the other?

Vedclass Test Series

Exam Paper Generator

Online Exam Module