List of top Physics Questions on Current electricity asked in AIIMS

In a potentiometer experiment of a cell of emf $1.25\, V$ gives balancing length of $30\, cm$. If the cell is replaced by another cell, balancing length is found to be $40\, cm$. What is the emf of second cell ?

In the circuit shown, the current through the 5 O resistor is

A current flows in a conductor only when there is an electric field within the conductor. The drift velocity of electron in presence of electric field decreases.

A square loop ABCD, carrying a current I, is placed near and coplanar with a long straight conductor XY carrying a current I, as shown in figure. The net force on the loop will be

Consider the diagram shown below.

A voltmeter of resistance $ 150 \,\Omega $ . is connected across $A$ and $B$. The potential drop across and $C$ measured by voltmeter is

The conductivity of an electrolyte is very low as compared to a metal at room temperature. The number density of free ions in electrolyte is much smaller as compared to number density of free electrons in metals. Further, ions drift much more slowly, being heavier.

A pure semiconductor has negative temperature coefficient of resistance. On raising the temperature, more charge carriers are released, conductance increases and resistance decreases.

A conducting rod of length $l$ and mass $m$ is moving down a smooth inclined plane of inclination $\theta$ with constant velocity $v$. A current $i$ is flowing in the conductor in a direction perpendicular to paper inwards. A vertically upwards magnetic field $\vec{ B }$ exists in space. Then magnitude of magnetic field $\vec{ B }$ is

The equivalent resistance between the points $X$ and $Y$ in the following circuit diagram will be

Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R
Assertion (A): A bird perches on a high power line and nothing happens to the bird.
Reason (R): The level of bird is very high from the ground.
In the light of the above statements, choose the correct answer from the options given below

Ohm?? law is applicable for all conducting elements. Ohm?? law is a fundamental law.

A larger dry cell has higher emf. The emf of a dry cell is proportional to its size.

A wire of length $L$ is drawn such that its diameter is reduced to half of its original diameter. If the initial resistance of the wire were $10\, \Omega$ , its new resistance would be

Electric appliances with metallic body e.g., heaters, presses etc., have three pin connections, whereas an electric bulb has a two pin connection. Three pin connections reduce heating of connecting cables.

A $60\, W$ incandescent lamp operates at $120\, V$. The number of electrons passing through the filament per second will be

What is the current (I) in the circuit, as shown in figure

Thermocouple thermometer is based on

Ten identical cells each of potential $E$ and internal resistance $r$ are connected in series to form a closed circuit. An ideal voltmeter connected across three cells, will read

A domestic electrical appliance, working on a three pin will continue working even if the top pin is removed. The third pin is used only as a safety device.

The internal resistance of a cell of e.m.f. $2$ volts is $0.1 \Omega$. It is connected to a resistance of $3.9$ $\Omega$. The voltage across the cell will be (in volts)

Ten identical wires each having a resistance of one ohm are connected in parallel. The combination will have a resistance of

What is the equivalent resistance between A and B in the given figure

Which of the following relation is called as current density ?