Current Electricity Practice Questions

Two resistors of 200 Ω and 400 Ω are connected in series with a battery of 100 V. A bulb rated at across the 200 V, 100 W is connected 400 Ω resistance. The potential drop across the bulb is _______V.[JEE Main 2 apr 2026 Shift 2]

Refer to the circuit diagram given below. The heat generated across the 6 Ω resistance in 100 second is $\;\frac{\alpha }{100} J$. The value of α is _______. (Nearest integer)[JEE Main 6 Apr 2026 shift 1]

In a meter bridge experiment to determine the value of unknown resistance, first the resistances $2 Ω$ and $3 Ω$ are connected in the left and right gaps of the bridge and the null point is obtained at a distance $l cm$ from the left. Now when an unknown resistance $x Ω$ is connected in parallel to $3 Ω$ resistance, the null point is shifted by 10 cm to the right of wire. The value of unknown resistance $x$ is $\_\_\_\_$ $Ω$.

A voltmeter with internal resistance of x Ω can be used to measure upto 20 V. In order to increase its measuring range to 30 V, the required modification is to ________.[JEE Main 4 Apr 2026 Shift 1]

Two resistors $2 Ω$ and $3 Ω$ are connected in the gaps of bridge as shown in figure. The null point is obtained with the contact of jockey at some point on wire $X Y$. When an unknown resistor is connected in parallel with $3 Ω$ resistor, the null point is shifted by 22.5 cm toward $Y$. The resistance of unknown resistor is $\_\_\_\_$ $Ω$.

An electric power line having total resistance of $2 Ω$, delivers 1 kW of power at 250 V - The percentage efficiency of transmission line is $\_\_\_\_$ .

To compare EMF of two cells using potentiometer the balancing lengths obtained are 200 cm and 150 cm . The least count of scale is 1 cm . The percentage error in the ratio of EMFs is $\_\_\_\_$

Sliding contact of a potentiometer is in the middle of the potentiometer wire having resistance $R_p=1 Ω$ as shown in the figure. An external resistance of $R_e=2 Ω$ as connected via the sliding contact. The electric current in the circuit is :

There are $n$ number of identical electric bulbs, each is designed to draw a power $p$ independently from the mains supply. They are now joined in series across the mains supply. The total power drawn by the combination is

The battery of a mobile phone is rated as 4.2 V , 5800 mAh . How much energy is stored in it when fully charged?

The value of current $l$ in the electrical circuit as given below, when potential at $A$ is equal to the potential at $B$, will be ______ A.

In the figure shown below, a resistance of $150.4 Ω$ is connected in series to an ammeter A of resistance $240 Ω$. A shunt resistance of $10 Ω$ is connected in parallel with the ammeter. The reading of the ammeter is $\_\_\_\_$ mA .

Find the equivalent resistance between two ends of the following circuit

Consider a moving coil galvanometer (MCG): A. The torsional constant in moving coil galvanometer has dimentions $[{\text{ML}}^2 {\text{T}}^{-2} ]\B. Increasing the current sensitivity may not necessarily increase the voltage sensitivity. C. If we increase number of turns $( {\text{N}})$ to its double $(2 {\text{N}})$, then the voltage sensitivity doubles. D. MCG can be converted into an ammeter by introducing a shunt resistance of large value in parallel with galvanometer. E. Current sensitivity of MCG depends inversely on number of turns of coil.Choose the correct answer from the options given below:

The net current flowing in the given circuit is_____ A.

Given below are two statements : Statement-I : The equivalent emf of two nonideal batteries connected in parallel is smaller than either of the two emfs. Statement-II : The equivalent internal resistance of two nonideal batteries connected in parallel is smaller than the internal resistance of either of the two batteries. In the light of the above statements, choose the correct answer from the options given below.

Current passing through a wire as function of time is given as $l(t)=0.02 t+0.01 {\text{A}}$. The charge that will flow through the wire from $t=1 {\ s}$ to $t=2 {\ s}$ is

A motor operating on 100 V draws a current of 1 A . If the efficiency of the motor is $91.6 \%$, then the loss of power in units of ${\text{cal}} / {\ s}$ is

Which of the following resistivity $(\rho ) {\text{v}} / {\ s}$ temperature ( $T$ ) curves is most suitable to be used in wire bound standard resistors?