Combination of Inductors, LR & LC Circuits

By combining three inductances, $2$ H, $4$ H and $6$ H, the minimum value of effective inductance that can be obtained is (in H)

Two inductors, $L_1$ and $L_2$ are connected in parallel and a time varying current flows as shown in the figure. The ratio of currents $\frac{I_2}{I_1}$ at any time, it is

Two inductors, $L_1$ and $L_2$, are connected in parallel and time-varying current flows the combination. If $I_1$ and $I_2$ are the currents passing through the inductor $L_1$ and $L_2$ respectively, the ratio $\frac{I_2}{I_1}$ is

The equivalent inductance between A and B is equal to

Three coils of inductance, $L_1$ = 2 H, $L_2$ = 3 H and $L_3$ = 6 H are connected so that they are separated from each other. To obtain the effective inductance of $\frac{18}{11}$ H between points A and B, out of the following figures, the correct one is

Two identical inductors are connected in two different configurations $P$ and $Q$, where a time varying current $I(t)$ is flowing, as shown in the figure. The induced emf between points $a$ and $b$ for configuration $P$ is $E_P$ and that for configuration $Q$ is $E_Q$. The ratio $E_P / E_Q$ is:

[Neglect the effect of mutual inductance.]

In the given circuit, if $dI/dt = -1$ A/s then the value of $V_{AB}$ at this instant will be

The following figure represents two bulbs $B_1$ and $B_2$, resistor R and an inductor L. When the switch S is turned off, which of the following statement is true?

An inductor of inductance 10 mH having resistance of $100\,\Omega$ is connected to battery of E.M.F. 1.0 V through a switch as shown in the figure below. After switch is closed, the ratio of instantaneous voltages across the inductor when the current passing through it is 2 mA and 4 mA is ______.

Figure shows the circuit that contains three resistances ( $9\,\Omega$ each) and two inductors ( 4 mH each). The reading of ammeter at the moment switch $K$ is turned ON, is ______ A.

In the given circuit below inductance values of $L_1, L_2$ and $L_3$ are same. The magnetic energy stored in the entire circuit is $(U_t)$ and that stored in the $L_2$ inductor is $(U_l) \cdot U_t / U_l$ is ______. (Ignore the mutual inductance if any)

In the circuit shown, when the current '$i$' is $3$A and increasing at the rate of $1$A/s the measurement of the potential difference between A and B is $12$ V. But when the same current $3$A is decreasing at the rate of $1$A/s, the measured potential difference $V_{AB}$ between A and B is $6$V. The value of 'R' in the circuit is

The equivalent inductance between A and B is equal to

Two identical coils of inductance $L$ joined in series are placed very close to each other such that the winding direction of one coil is exactly opposite to that of the other. The net inductance is

Three inductances are connected as shown in the figure. The equivalent inductance between A and B is

$AB$ is a part of an electrical circuit (see figure). The potential difference " $V_A - V_B$ ", at the instant when current $i = 2\text{ A}$ and is increasing at a rate of $1\text{ amp/}$ second is:

In the given circuit the sliding contact is pulled outwards such that electric current in the circuit changes at the rate of $8\text{ A/s}$. At an instant when R is $12\,\Omega$, the value of the current in the circuit will be ________ A.

An inductor coil of inductance $L$ is divided into two parts and both parts are connected in parallel. The net inductance is

Consider the following circuit. By keeping $S_1$ closed, the capacitor is fully charged and then $S_1$ is opened and $S_2$ is closed, then

Three coils of inductance $L_1 = 2\text{ H}, L_2 = 3\text{ H}$ and $L_3 = 6\text{ H}$ are connected such that they are separated from each other. To obtain the effective inductance of 1 henry, out of the following combinations as shown in figure, the correct one is

As per the given figure, if $\frac{dI}{dt} = -1\text{ A/s}$ then the value of $V_{AB}$ at this instant will be ____________ $\text{V}$.

Three identical resistors with resistance R = 12$\Omega$ and two identical inductors with self inductance L = 5 mH are connected to an ideal battery with emf of 12 V as shown in figure. The current through the battery long after the switch has been closed will be _____________ A.

Two coils of self inductance L1 and L2 are connected in series combination having mutual inductance of the coils as M. The equivalent self inductance of the combination will be:

For the given circuit the current through battery of 6 V just after closing the switch 'S' will be _________ A.

An inductor coil stores 64 J of magnetic field energy and dissipates energy at the rate of 640 W when a current of 8A is passed through it. If this coil is joined across an ideal battery, find the time constant of the circuit in seconds:

The time taken for the magnetic energy to reach 25% of its maximum value, when a solenoid of resistance R, inductance L is connected to a battery, is:

Figure shows a circuit that contains four identical resistors with resistance R = 2.0$\Omega$, two identical inductors with inductance L = 2.0 mH and an ideal battery with emf E = 9V. The current 'i' just after the switch 'S' is closed will be:

A circuit has self-inductance 'L' H and carries a current 'I' A. To prevent sparking when the circuit is switched off, a capacitor which can withstand 'V' volt is used. The least capacitance of the capacitor connected across the switch must be equal to

A part of a complete circuit is shown in the figure. At some instant, the value of current I is 1A and it is decreasing at a rate

of 102 A s–1. The value of the potential difference VP – VQ, (in volts) at that instant, is _________.

A shown in the figure, a battery of emf $\varepsilon$ is connected to an inductor L and resistance R in series. The switch is closed at t = 0. The total charge that flows from the battery, between t = 0 and t = tc (tc is the time constant of the circuit) is:

A 20 Henry inductor coil is connected to a 10 ohm resistance in series as shown in figure. The time at which rate of dissipation of energy (joule's heat) across resistance is equal to the rate at which magnetic energy is stored in the inductor is:

An ideal coil of $10\text{ H}$ is connected in series with a resistance of $5\,\Omega$ and a battery of $5\text{ V} \cdot 2$ second after the connection is made, the current flowing in ampere in the circuit is

An inductor $(L = 100\text{ mH})$, a resistor $(R = 100\,\Omega)$ and a battery $(E = 100\text{ V})$ are initially connected in series as shown in the figure. After a long time the battery is disconnected after short circuiting the points $A$ and $B$. The current in the circuit $1\text{ ms}$ after the short circuit is

A coil of inductance $300\text{ mH}$ and resistance $2\,\Omega$ is connected to a source of voltage $2\text{ V}$. The current reaches half of its steady state value in

The inductance between $A$ and $D$ is