Electrical Resistance

If we plot the Current as a function of voltage then we will get a _____  passing through origin.

A wire of given material having length $l$ and area of cross-section $A$ has a resistance of $4 \mathrm{\Omega }$. What would be the resistance of another wire of the same material having length $l/2$ and area of cross-section $2A$?

A wire of resistance 1 ohm is stretched so as to change its diameter by 0.25%. The percentage change in its resistance is

If an equilateral triangle is made of a uniform wire of resistance R, the equivalent resistance between the ends of sides is

If equivalent resistances of R1 and R2 in series and parallel be r1 and r2 respectively, then $\frac{R_1}{R_2}$ equal

If the variable resistances are connected to a cell of constant e.m.f. then which of the following graph represents the relationship between current I and resistance R?

If reading of ammeter is 2A then what is value of X in ohm's?

To verify Ohm's law, a student is provided with a test resistor$R_T$, a high resistance $R_1$, a small resistance $R_2$, two identical galvanometers $G_1$ and $G_2$, and a variable voltage source $V$. The correct circuit to carry out the experiment is

Two identical cells whether connected in parallel or in series gives the same current when connected to an external resistance $1.5\Omega .$ Find the value of internal resistance of each cell.

The figure given below shows a network of eight resistors, each equal to $2 \mathrm{\Omega },$ connected to a $3 \mathrm{V}$ battery of negligible internal resistance. The current $I$ in the circuit is 

The following graph shows the current versus voltage values of some unknown conductor. What is the resistance of this conductor?

In the figure, the reading on the ammeter is $2.4 \mathrm{A}$ and the reading on the voltmeter is $6.0 \mathrm{V}$. Calculate the resistance of the metallic conductor.

Connecting an ammeter and a voltmeter to determine the resistance of a metallic conductor in a circuit.

Calculate the resistance of a lamp carrying a current of $0.40 \mathrm{A}$ when connected to a $230 \mathrm{V}$ supply.

A solid metallic cuboid of homogeneous material having geometrical dimension as shown in the figure will have a ratio of resistances for the sense of current along $x$, $y$ and $z$ directions respectively, equal to

Which of the following quantities can have SI unit $\mathrm{kg} {\mathrm{m}}^2 {\mathrm{A}}^{-2} {\mathrm{s}}^{-3}$?

Electrical resistivity of a given metallic wire depends upon

In an electric circuit, a device called rheostat is often used to change the _____ in the circuit.

If the potential difference across the two ends of a conductor is $1 \mathrm{V}$ and the current through it is $1 \mathrm{A}$, then the resistance R, of the conductor is :

A conductor with rectangular cross-section has dimensions $\left(\mathrm{a}\times 2\mathrm{a}\times 4\mathrm{a}\right)$ as shown in the figure. Resistance across $\mathrm{A}\mathrm{B}$ is $\mathrm{x}$, across $\mathrm{C}\mathrm{D}$ is $\mathrm{y}$ and across $\mathrm{E}\mathrm{F}$ is $\mathrm{z}$. Then -
.

Reciprocal of the specific resistance is -