List of top Physics Questions on Electric Current asked in JEE Main

An element \(\triangle l=\triangle x \hat i\) is placed at the origin and carries a large current I = 10A. The magnetic field on the y-axis at a distance of 0.5 m from the elements x of 1 cm length is :

The number of electrons flowing per second in the filament of a 110 W bulb operating at 220 V is: (Given $e = 1.6 \times 10^{-19}$ C)

An electric bulb rated 50 W – 200 V is connected across a 100 V supply. The power dissipation of the bulb is :

In the following circuit, the battery has an emf of \(2 \, \text{V}\) and an internal resistance of \(\frac{2}{3} \, \Omega\). The power consumption in the entire circuit is ______ W.

Find average power in electric circuit if source voltage \((V) = 20\;sin(100\;⍵t)\) and current in the circuit \((I) = 2\;sin\;\bigg(100⍵t + \frac{\pi}{3}\bigg)\)

If electric current passing through a conductor varies with time as \(I = 10 + A \;ẞt\), where \(I_o = 20 A\), \(B = \frac{3A}{S}\), then find charge flow through the conductor in first \(10\) sec is

The charge flowing in a conductor changes with time as $Q(t)=\alpha t-\beta t ^2+\gamma^3$ Where $\alpha, \beta$ and $\gamma$ are constants Minimum value of current is :

A hollow cylindrical conductor has length of $314\, m$, while its inner and outer diameters are $4 \, mm$ and $8 \, mm$ respectively The resistance of the conductor is $n \times 10^{-3} \Omega$.If the resistivity of the material is $24 \times 10^{-8} \Omega m$ The value of $n$ is ___

Sound travels in a mixture of two moles of helium and $n$ moles of hydrogen If rms speed of gas molecules in the mixture is $\sqrt{2}$ times the speed of sound, then the value of $n$ will be

A cell of emf 90 V is connected across a series combination of two resistors, each of 100 \( \Omega \) resistance. A voltmeter of resistance 400 \( \Omega \) is used to measure the potential difference across each resistor. The reading of the voltmeter will be:

If the length of a conductor is increased by 20% and cross-sectional area is decreased by 4% , then calculate the percentage change in the resistance of the conductor.

If the length of a conductor is increased by 20% and cross-sectional area is decreased by 4% ,then calculate the percentage change in the resistance of the conductor.

Given below are two statement :  
Statement I : If the number of turns in the coil of a moving coil galvanometer is doubled then the current sensitivity becomes double.  
Statement II : Increasing current sensitivity of a moving coil galvanometer by only increasing the number of turns in the coil will also increase its voltage sensitivity in the same ratio.
In the light of the above statement, choose the correct answer from the options given below : 

The length of a conductor having resistance 160 Ω, is compressed to 25% of its initial value. The new resistance will be

For the given figures, choose the correct options:

For a given transistor amplifier circuit in CE configuration V_CC = 1 V, R_c = 1 kΩ, R_b = 100 kΩ and β = 100. Value of base current I_b is

A straight wire carrying of 14 A is bent into a semi-circular arc of radius 2.2 cm as shown in the figure. The magnetic field produced by the current at the centre (O) of the arc is ____ × 10^–4 T.

Given below are two statements:
Statement I : An AC circuit undergoes electrical resonance if it contains either a capacitor or an inductor. 
Statement II : An AC circuit containing a pure capacitor or a pure inductor consumes high power due to its non-zero power factor.
In the light of above statements, choose the correct answer from the options given below :

The equivalent resistance between points A and B in the given network is:
 

A zener of breakdown voltage V_Z = 8 V and maximum Zener current, I_ZM = 10 mA is subjected to an input voltage V_i = 10 V with series resistance R = 100 Ω. In the given circuit R_L represents the variable load resistance. The ratio of maximum and minimum value of R_L is __________.

The current I in the given circuit will be

A resistor develops 300 J of thermal energy in 15 s, when a current of 2 A is passed through it. If the current increases to 3 A, the energy developed in 10 s is ______ J.

The total current supplied to the circuit as shown in figure by the 5 V battery is _______ A.

Resistances are connected in a meter bridge circuit as shown in the figure. The balancing length l₁ is 40 cm. Now an unknown resistance x is connected in series with P and new balancing length is found to be 80 cm measured from the same end. Then the value of x will be ________ Ω.