JEE EMF & Circuit Analysis PYQs with Solutions, Download PDF

A series LCR circuit with $$L = \frac{100}{\pi}$$ mH, $$C = \frac{10^{-3}}{\pi}$$ F and $$R = 10$$ $$\Omega$$, is connected across an AC source of 220 V, 50 Hz supply. The power factor of the circuit would be _____.

A current of $$15 \text{ mA}$$ flows in the circuit as shown in figure. The value of potential difference between the points $$A$$ and $$B$$ will be

A galvanometer of resistance $$G$$ is converted into a voltmeter of range $$0 - 1\,\text{V}$$ by connecting a resistance $$R$$ in series with it. The additional resistance that should be connected in series with $$R_1$$ to increase the range of the voltmeter to $$0 - 2\,\text{V}$$ will be:

Four resistances 40 $$\Omega$$, 60 $$\Omega$$, 90 $$\Omega$$, 110 $$\Omega$$ and make the arms of a quadrilateral ABCD. Across AC is a battery of emf 40 V and internal resistance negligible. The potential difference across BD in V 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______

The net current flowing in the given circuit is_______ A.
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The current $$i$$ in the network is:

In the given circuit the value of $$\left|\frac{I_1+I_3}{I_2}\right|$$ is:

The value of current in the 6 $$\Omega$$ resistance is:

A cell of emf 90 V is connected across 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:

A galvanometer, whose resistance is 50 ohm, has 25 divisions in it. When a current of $$4 \times 10^{-4}$$ A passes through it, its needle (pointer) deflects by one division. To use this galvanometer as a voltmeter of range 2.5 V it should be connected to a resistance of:

A battery of $$6 \text{ V}$$ is connected to the circuit as shown below. The current $$I$$ drawn from the battery is

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

The value of current $$i_1$$ flowing from A to C in the circuit diagram is:

In the figure shown, the current in the $$10\,\text{V}$$ battery is close to:

First, a set of $$n$$ equal resistors of 10 $$\Omega$$ each are connected in series to a battery of E.M.F. 20 V and internal resistance 10 $$\Omega$$. A current $$I$$ is observed to flow. Then, the $$n$$ resistors are connected in parallel to the same battery. It is observed that the current is increased 20 times, then the value of $$n$$ is _________.

Which of the following statements is false?

In the following circuit $$C_1 = 12$$ $$\mu F$$, $$C_2 = C_3 = 4$$ $$\mu F$$ and $$C_4 = C_5 = 2$$ $$\mu F$$. The charge stored in $$C_3$$ is ______ $$\mu C$$.

A moving coil galvanometer has resistance 50 $$\Omega$$ and it indicates full deflection at 4 mA current. A voltmeter is made using this galvanometer and a 5 k$$\Omega$$ resistance. The maximum voltage, that can be measured using this voltmeter, will be close to:

A galvanometer of resistance 100 Ω has 50 divisions on its scale and has sensitivity of 20 μA/division. It is to be converted to voltmeter with three ranges, of 0 - 2 V, 0 - 10 V and 0 - 20 V. The appropriate circuit to do so is:

In a circuit shown in the figure, the capacitor $$C$$ is initially uncharged and the key $$K$$ is open. In this condition, a current of 1 A flows through the 1 $$\Omega$$ resistor. The key is closed at time $$t = t_0$$. Which of the following statement(s) is(are) correct?

[Given: $$e^{-1} = 0.36$$]

The resistance of a galvanometer is 50 ohm and the maximum current which can be passed through it is 0.002 A. What resistance must be connected to it in order to convert it into an ammeter of range 0 - 0.5 A?

The circuit shown here has two batteries of 8.0 V and 16.0 V and three resistors 3$$\Omega$$, 9$$\Omega$$ and 9$$\Omega$$ and a capacitor of 5.0 $$\mu$$F. How much is the current I in the circuit in steady state?

On interchanging the resistances, the balance point of a meter bridge shifts to the left by 10 cm. The resistance of their series combination is 1 k$$\Omega$$. How much was the resistance on the left slot before interchanging the resistances?

Two batteries with e.m.f. 12 V and 13 V are connected in parallel across a load resistor of 10 $$\Omega$$. The internal resistance of the two batteries are 1 $$\Omega$$ and 2 $$\Omega$$ respectively. The voltage across the load lies between,

An ideal battery of emf 4V and resistance R are connected in series in the primary circuit of a potentiometer of length 1 m and resistance $$5\Omega$$. The value of R, to give a potential difference of 5 mV across 10 cm of potentiometer wire, is:

Consider a 72 cm long wire AB as shown in the figure. The galvanometer jockey is placed at P on AB at a distance $$x$$ cm from A. The galvanometer shows zero deflection.

The value of $$x$$, to the nearest integer, is ___.

A 16 $$\Omega$$ wire is bent to form a square loop. A 9 V supply having an internal resistance of 1 $$\Omega$$ is connected across one of its sides. The potential drop across the diagonals of the square loop is _________ $$\times 10^{-1}$$ V.

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

Refer to the circuit diagram given below. The heat generated across the 6 $$\Omega$$ resistance in 100 second is $$\frac{\alpha}{100}$$ J. The value of $$\alpha$$ is _______. (Nearest integer)