According to Joule's law,if the potential dif | vedclass

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

Question

(D) The power dissipated as heat in a conductor is given by $P = \frac{V^2}{R}$.We know that the resistance $R$ of a conductor is given by $R = \frac{

Vedclass · Accepted Answer

$\frac{1}{\rho}$

Vedclass · Answer

(D) The power dissipated as heat in a conductor is given by $P = \frac{V^2}{R}$.We know that the resistance $R$ of a conductor is given by $R = \frac{\rho l}{A}$,where $\rho$ is the specific resistance (resistivity),$l$ is the length,and $A$ is the cross-sectional area.Substituting the expression for $R$ into the power formula,we get $P = \frac{V^2}{(\rho l / A)} = \frac{A V^2}{\rho l}$.Given that the potential difference $V$,length $l$,and cross-sectional area $A$ are constant,the term $\frac{A V^2}{l}$ is a constant.Therefore,$P \propto \frac{1}{\rho}$.Thus,the heat produced is directly proportional to $\frac{1}{\rho}$.

According to Joule's law,if the potential difference across a conductor having a material of specific resistance remains constant,then the heat produced in the conductor is directly proportional to

Similar Questions

The number of electrons flowing per second in the filament of a $110 \,W$ bulb operating at $220 \,V$ is : (Given $e=1.6 \times 10^{-19} \,C$ )

An electric kettle takes $4\, A$ current at $220\, V$. How much time will it take to boil $1\, kg$ of water from room temperature $20\, ^\circ C$? The temperature of boiling water is $100\, ^\circ C$. (Assume specific heat of water $c = 4200\, J/kg\, ^\circ C$)

If the length of the filament of a heater is reduced by $10\%$,the power of the heater will

$A$ $12 \text{ HP}$ motor has to be operated $8 \text{ hours/day}$. How much will it cost at the rate of $50 \text{ paisa/kWh}$ in $10$ days? (in $Rs.$)

An electric bulb is designed to draw power $P_0$ at voltage $V_0$. If the voltage is $V$,it draws a power $P$. Then:

Vedclass Test Series

Exam Paper Generator

Online Exam Module