Current Electricity

The stored charge in the capacitor in steady state of the following circuit is μC. [figure]

Refer to the circuit diagram given below. The heat generated across the 6 resistance in 100 second is 100 J. The value of is . (Nearest integer) [figure]

Two cells of emfs 1 V and 2 V and internal resistance 2 and 1 , respectively connected in parallel, gave a current of 1 A through an external resistance. If the polarity of one cell is reversed, then value of current through the external resistance will be 5 A. The value of is .

When an external resistance of 5 is connected across terminals of a cell, a current of 0.25 A flows through it. When the 5 resistor is replaced by a 2 resistor, a current of 0.5 A flows through it. The internal resistance of the cell is .

The equivalent resistance between the points A and B in the following circuit is x5 . The value of x is . [figure]

In a meter bridge experiment to determine the value of unknown resistance, first the resistances 2 and 3 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 is connected in parallel to 3 resistance, the null point is shifted by 10 cm to the right of wire. The value of unknown resistance x is .

A cylindrical conductor of length 2 m and area of cross-section 0.2 mm2 carries an electric current of 1.6 A when its ends are connected to a 2 V battery. Mobility of electrons in the conductor is 10-3 m2/V s. The value of is : (electron concentration = 5 1028 /m3 and electron charge = 1.6 10-19 C)

The heat generated in 1 minute between points A and B in the given circuit, when a battery of 9 V with internal resistance of 1 is connected across these points is J. [figure]

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

Two cells of emfs 1 V and 2 V and internal resistances 2 and 1 , respectively, are connected in series with an external resistance of 6 . The total current in the circuit is I1. Now the same two cells in parallel configuration are connected to same external resistance. In this case, the total current drawn is I2. The value of ( I1I2 ) is x3. The value of x is .

The value of current I in the electrical circuit as given below, when potential at A is equal to the potential at B, will be A. [figure]

A wire of resistance 9 is bent to form an equilateral triangle. Then the equivalent resistance across any two vertices will be ohm.

At steady state the charge on the capacitor, as shown in the circuit below, is . [figure]

The net current flowing in the given circuit is A. [figure]

The current flowing through the 1 resistor is n10 A. The value of n is . [figure]

To determine the resistance (R) of a wire, a circuit is designed below. The V-I characteristic curve for this circuit is plotted for the voltmeter and the ammeter readings as shown in figure. The value of R is . [figure]

At room temperature (27 ), the resistance of a heating element is 50 . The temperature coefficient of the material is 2.4 10-4 C-1. The temperature of the element, when its resistance is 62 , is .

Resistance of a wire at 0 , 100 and t is found to be 10 , 10.2 and 10.95 respectively. The temperature t in Kelvin scale is .

A heater is designed to operate with a power of 1000 W in a 100 V line. It is connected in combination with a resistance of 10 and a resistance R, to a 100 V mains as shown in figure. For the heater to operate at 62.5 W, the value of R should be . [figure]

A wire of resistance R and radius r is stretched till its radius became r/2. If new resistance of the stretched wire is x R, then value of x is .

The electric field between the two parallel plates of a capacitor of 1.5 capacitance drops to one third of its initial value in 6.6 when the plates are connected by a thin wire. The resistance of this wire is . (Given, e 3 = 1.1)

A wire of resistance 20 is divided into 10 equal parts. A combination of two parts are connected in parallel and so on. Now resulting pairs of parallel combination are connected in series. The equivalent resistance of final combination is .

Twelve wires each having resistance 2 are joined to form a cube. A battery of 6 V emf is joined across points a and c. The voltage difference between e and f is V. [figure]

Two wires A and B are made up of the same material and have the same mass. Wire A has radius of 2.0 mm and wire B has radius of 4.0 mm. The resistance of wire B is 2 . The resistance of wire A is .

The current in a conductor is expressed as I = 3t2 + 4t3, where I is in Ampere and t is in second. The amount of electric charge that flows through a section of the conductor during t = 1 s to t = 2 s is C.

In an electrical circuit drawn below the amount of charge stored in the capacitor is . [figure]

Equivalent resistance of the following network is . [figure]

In the following circuit, the battery has an emf of 2 V and an internal resistance of 23 . The power consumption in the entire circuit is W. [figure]

Two cells are connected in opposition as shown. Cell E1 is of 8 V emf and 2 internal resistance; the cell E2 is of 2 V emf and 4 internal resistance. The terminal potential difference of cell E2 is V. [figure]

Two resistances of 100 and 200 are connected in series with a battery of 4 V and negligible internal resistance. A voltmeter is used to measure voltage across 100 resistance, which gives reading as 1 V. The resistance of voltmeter must be .