Temperature Dependence of Resistivity

The conductivity of a material varies with temperature for (i) semiconductors and (ii) good conductors as

The resistance of platinum wire at $0 °\mathrm{C}$ is $2 \mathrm{\Omega }$ and $6.8 \mathrm{\Omega }$ at $80 °\mathrm{C}$. The temperature coefficient of resistance of the wire is:

The current flowing through a conductor connected across a source is $2 \mathrm{A}$ and $1.2 \mathrm{A}$ at $0^{\mathrm{o}}\mathrm{C}$ and ${100}^{\mathrm{o}}\mathrm{C}$ respectively. The current flowing through the conductor at ${50}^{\mathrm{o}}\mathrm{C}$ will be _____ $\times {10}^2 \mathrm{mA}$.

Given below are two statements:

Statement I : The equivalent resistance of resistors in a series combination is smaller than least resistance used in the combination.

Statement II : The resistivity of the material is independent of temperature. In the light of the above statements, choose the correct answer from the options given below:

Constantan wire is used in making standard resistance because its

The resistance of a wire is $60 \mathrm{ohm}$. It is connected in series to a wire of different material. Calculate the resistance of the second wire so that their combined resistance does not change with temperature. The temperature coefficient of resistance for first and the second wire are respectively $3\times {10}^{-3}{ }^{\circ }{\mathrm{C}}^{-1}$ and $-1.5\times {10}^{-3}{ }^{\circ }{\mathrm{C}}^{-1}$.

A brass disc and a carbon disc of same radius are assembled alternatively to make a cylindrical conductor. The resistance of the cylinder is independent of the temperature. The ratio of thickness of the brass disc to that of the carbon disc is

[$\alpha$ is temperature coefficient of resistance & Neglect linear expansion]

Resistance of wire at $20°\mathrm{C}$ is $10 \mathrm{\Omega }$. At what temperature, resistance becomes $30 \mathrm{\Omega }$ (The temperature coefficient of resistance $\alpha =0.0125 °{\mathrm{C}}^{-1}$)

Wires $P$ and $Q$ are having same resistance at room temperature. When heated, resistance of $P$ increases, and that of $Q$ decreases, we conclude that

The resistance of a metal wire is $5 \mathrm{\Omega }$ and $6 \mathrm{\Omega }$ at $50 °\mathrm{C}$ and $100 °\mathrm{C}$, respectively. The temperature at which the resistance is $7 \mathrm{\Omega }$ is

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R.

Assertion A: Alloys such as constantan and manganin are used in making standard resistance coils.

Reason R: Constantan and manganin have very small value of temperature coefficient of resistance.

In the light of the above statements, choose the correct answer from the options given below.

The resistance at ${300}^{\circ }\mathrm{C}$ is $100 \mathrm{\Omega }$. Find the temp at which resistance will become $150 \mathrm{\Omega }$, if $\propto =0.04$.

Resistance of the wire is measured as $2 \mathrm{\Omega }$ and $3 \mathrm{\Omega }$ at $10°\mathrm{C}$ and $30°\mathrm{C}$ respectively. Temperature coefficient of resistance of the material of the wire is

The resistance of a thin silver wire is $1.0 \mathrm{\Omega }$ at $20°\mathrm{C}$. The wire is placed in a liquid bath and its resistance rises to $1.2 \mathrm{\Omega }$. What is the temperature of the bath?
(Take, $\alpha$ for silver $=3.8\times {10}^{-3}$ per ${}^{\circ }\mathrm{C}$)

A coil has a resistance of $80\mathrm{\Omega }$ at $15°\mathrm{C}$, find it's resistance at $60°\mathrm{C}$ the temperature co efficient of resistance is $0.004/°\mathrm{C}$?

The resistance of the platinum wire of a platinum resistance thermometer at an ice point is $5 \mathrm{\Omega }$ and at steam point is $5.23 \mathrm{\Omega }$. When the thermometer is inserted in a hot bath, the resistance of the platinum wire is $5.795 \mathrm{\Omega }$. Calculate the temperature of the bath.

A temperature sensor is made of Platinum whose temperature co-efficient of resistance is $0.004{ \mathrm{K}}^{-1}$(i.e. per degree Kelvin). A person uses a wire of Platinum whose resistance is $100\mathrm{\Omega }$ at $T=273 \mathrm{K}.$ A constant current of $10 \mathrm{mA}$ is passed through the wire and the voltage developed across this is measured. The person must choose a voltmeter that has sufficient resolution so that a temperature difference $\Delta T=0.1 \mathrm{K}$ around room temperature can be measured. Which of the following is CORRECT?

How resistivity varies with temperature for semiconductor insulator and conductor?

Do insulators have resistivity?

What is the effect of temperature on the resistivity of a conductor?