Resistivity

The resistivity of copper metal depends on only one of the following factors. This factor is:

The resistivity of a certain material is $0.6 \mathrm{\Omega } \mathrm{m}$. The material is most likely to be:

If the resistance of a certain copper wire is $1 \mathrm{\Omega }$, then the resistance of a similar nichrome wire will be about:

The electrical resistivities of four materials $P, Q, R$ and $S$ are given below:
$P 6.84\times {10}^{-8} \mathrm{\Omega m}$
$Q 1.70\times {10}^{-8} \mathrm{\Omega m}$
$R 1.0\times {10}^{15} \mathrm{\Omega m}$
$S 11.0\times {10}^{-7} \mathrm{\Omega m}$
Which material will you use for making: (a) heating element of electric iron (b) connecting wires of electric iron (c) covering of connecting wires? Give a reason for your choice in each case.

The electrical resistivities of four materials $\mathrm{A},\mathrm{B},\mathrm{C}$ and $\mathrm{D}$ are given below:
$\mathrm{A} 110\times {10}^{-8} \mathrm{\Omega m}$
$\mathrm{B} 1.0\times {10}^{10} \mathrm{\Omega m}$
$\mathrm{C} 10.0\times {10}^{-8} \mathrm{\Omega m}$
$\mathrm{D} 2.3\times {10}^3 \mathrm{\Omega m}$
Which material is: (a) good conductor (b) resistor (c) insulator and (d) semiconductor?

The electrical resistivities of three materials $P,Q$ and $R$ are given below:
$P 2.3\times {10}^3 \mathrm{\Omega m}$
$Q 2.63\times {10}^{-8} \mathrm{\Omega m}$
$R 1.0\times {10}^{15} \mathrm{\Omega m}$
Which material will you use for making (a) electric wires, (b) handle for soldering iron, and (c) solar cells? Give reasons for your choices.

The resistance of a metal wire of length $1 \mathrm{m}$ is $26 \mathrm{\Omega }$ at $20°\mathrm{C}.$ If the diameter of the wire is $0.3 \mathrm{mm},$ what will be the resistivity of the metal at that temperature?

Distinguish between resistance and resistivity.

State the SI unit of resistivity.

Define resistivity. Write an expression for the resistivity of a substance. Give the meaning of each symbol which occurs in it.

Calculate the resistance of a copper wire $1.0 \mathrm{km}$ long and $0.50 \mathrm{mm}$ diameter if the resistivity of copper is $1.7\times {10}^{-8} \mathrm{\Omega m}$.

What will be the resistance of a metal wire of length $2 \mathrm{metres}$ and area of cross-section $1.55\times {10}^{-6} {\mathrm{m}}^2$, if the resistivity of the metal be $2.8\times {10}^{-8}\mathrm{\Omega m}$?

Write down an expression for the resistance of a metallic wire in terms of the resistivity.

A wire is $1.0 \mathrm{m}$ long, $0.2 \mathrm{mm}$ in diameter and has a resistance of $10 \mathrm{\Omega }$. Calculate the resistivity of its material.

What do you understand by the "resistivity" of a substance?

Which has less electrical resistance: a thin wire or a thick wire (of the same length and same material)?