In circuit shown below, the resistances are given in ohms and the battery is assumed ideal with emf equal to 3 volt. The voltage across the resistance R4 is:
1. 0.4 V
2. 0.6 V
3. 1.2 V
4. 1.5 V
A battery of e.m.f. E and internal resistance r is connected to a variable resistor R as shown below. Which one of the following is true?
1. | Potential difference across the terminals of the battery is maximum when R = r. |
2. | Power delivered to the resistor is maximum when R = r. |
3. | Current in the circuit is maximum when R = r. |
4. | Current in the circuit is maximum when R >> r. |
The current in the arm CD of the circuit will be:
1.
2.
3.
4.
Consider the circuit shown in the figure below. The current I3 is equal to:
1. 5 A
2. 3 A
3. –3 A
4. –5/6 A
For measurement of potential difference, the potentiometer is preferred in comparison to the voltmeter because:
1. the potentiometer is more sensitive than the voltmeter.
2. the resistance of the potentiometer is less than
the voltmeter.
3. the potentiometer is cheaper than the voltmeter.
4. the potentiometer does not take current from the circuit.
In the Wheatstone's bridge (shown in the figure below) X = Y and A > B. The direction of the current between a and b will be:
1. | from a to b. |
2. | from b to a. |
3. | from b to a through c. |
4. | from a to b through c. |
A resistance of 4 Ω and a wire of length 5 metres and resistance 5 Ω are joined in series and connected to a cell of e.m.f. 10 V and internal resistance 1 Ω. A parallel combination of two identical cells is balanced across 300 cm of the wire. The e.m.f. E of each cell is:
1. 1.5 V
2. 3.0 V
3. 0.67 V
4. 1.33 V
In the circuit given below, the e.m.f. of the cell is 2 volt and the internal resistance is negligible. The resistance of the voltmeter is 80 ohm. The reading of the voltmeter will be:
1. 0.80 volt
2. 1.60 volt
3. 1.33 volt
4. 2.00 volt
In the circuit shown below, E1 = 4.0 V, R1= 2 Ω, E2 = 6.0 V, R2 = 4 Ω and R3 = 2 Ω. The current I1 is:
1. 1.6 A
2. 1.8 A
3. 1.25 A
4. 1.0 A
The potential difference across 8 ohms resistance is 48 volts as shown in the figure below. The value of potential difference across X and Y points will be:
1. 160 volt
2. 128 volt
3. 80 volt
4. 62 volt