Which of the following wires made of the same | vedclass

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

Question

(C) The resistance $R$ of a wire is given by the formula $R = \rho \frac{l}{A} = \rho \frac{l}{\pi r^2}$,where $\rho$ is the resistivity,$l$ is the le

Vedclass · Accepted Answer

Radius $1 \, mm$ and length $80 \, m$.

Vedclass · Answer

(C) The resistance $R$ of a wire is given by the formula $R = \rho \frac{l}{A} = \rho \frac{l}{\pi r^2}$,where $\rho$ is the resistivity,$l$ is the length,and $r$ is the radius.Since all wires are made of the same material,$\rho$ is constant.For option $A$: $R_A \propto \frac{40}{1^2} = 40$.For option $B$: $R_B \propto \frac{40}{2^2} = 10$.For option $C$: $R_C \propto \frac{80}{1^2} = 80$.For option $D$: $R_D \propto \frac{80}{2^2} = 20$.Comparing the values,$R_C$ is the highest. Therefore,the wire with radius $1 \, mm$ and length $80 \, m$ has the highest resistance.

Which of the following wires made of the same material will have the highest resistance?

Similar Questions

$A$ wire of $1 \,\Omega$ has a length of $1\, m$. It is stretched until its length increases by $25\, \%$. The percentage change in resistance to the nearest integer is .....$\%$

Masses of three wires of copper are in the ratio of $1: 3: 5$ and their lengths are in the ratio of $5: 3: 1$. The ratio of their electrical resistances is

The coefficient of linear expansion of the material of a resistor is $\alpha$. Its temperature coefficient of resistivity and resistance are $\alpha_\rho$ and $\alpha_R$ respectively. Then the correct relation is:

$A$ wire is stretched to increase its length by $2\%$,then the percentage change in its resistance is . . . . . . . (in $\%$)

Two wires of equal diameters,of resistivities $\rho_1$ and $\rho_2$ and lengths $l_1$ and $l_2$,respectively,are joined in series. The equivalent resistivity of the combination is

Vedclass Test Series

Exam Paper Generator

Online Exam Module