A long straight wire of resistance R,radius a | vedclass

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

Question

(D) The electric field $E$ inside the wire is given by $E = \frac{V}{l} = \frac{IR}{l}$,where $V$ is the potential difference across the wire.The magn

Vedclass · Accepted Answer

$\frac{I^2R}{2\pi al}$

Vedclass · Answer

(D) The electric field $E$ inside the wire is given by $E = \frac{V}{l} = \frac{IR}{l}$,where $V$ is the potential difference across the wire.The magnetic field $B$ at the surface of the wire is given by Ampere's Law as $B = \frac{\mu_0 I}{2\pi a}$,where $a$ is the radius of the wire.The Poynting vector $S$ is defined as $S = \frac{1}{\mu_0} (E 	imes B)$. Since $E$ is parallel to the wire and $B$ is tangential,the magnitude of the Poynting vector is $S = \frac{EB}{\mu_0}$.Substituting the values of $E$ and $B$:$S = \frac{1}{\mu_0} \left( \frac{IR}{l} ight) \left( \frac{\mu_0 I}{2\pi a} ight) = \frac{I^2R}{2\pi al}$.This vector is directed radially inward,representing the energy flow into the wire to account for Joule heating.

$A$ long straight wire of resistance $R$,radius $a$,and length $l$ carries a constant current $I$. The Poynting vector for the wire will be

Similar Questions

$A$ parallel plate capacitor has a capacitance $C = 200 \ pF$. It is connected to a $230 \ V$ $AC$ supply with an angular frequency $\omega = 300 \ rad/s$. The $rms$ value of the conduction current in the circuit and the displacement current in the capacitor,respectively,are:

Due to the tilting of the Earth,which waves finally disappear?

If $11 \%$ of the power of a $200 \ W$ bulb is converted to visible radiation,then the intensity of the light at a distance of $100 \ cm$ from the bulb is (in $W \ m^{-2}$)

The energy that will be ideally radiated by a $100\,kW$ transmitter in $1$ hour is:

The power radiated from a linear antenna of length $l$ is proportional to (Given,$\lambda =$ wavelength of the wave):

Vedclass Test Series

Exam Paper Generator

Online Exam Module