A battery has e.m.f. 4 V and internal resistance r. When this battery is connected to an external resistance of 2 ohm, a current of 1 ampere flows in the circuit. How much current will flow if the terminals of the battery are connected directly?
1. | 1 A | 2. | 2 A |
3. | 4 A | 4. | Infinite |
In the circuit shown below, the cell has an e.m.f. of 10 V and internal resistance of 1 ohm. The other resistances are shown in the figure. The potential difference is :
(1) 6 V
(2) 4 V
(3) 2 V
(4) –2 V
In the circuit, the potential difference across PQ will be nearest to
(1) 9.6 V
(2) 6.6 V
(3) 4.8 V
(4) 3.2 V
The e.m.f. of a cell is E volts and internal resistance is r ohm. The resistance in external circuit is also r ohm. The p.d. across the cell will be
(1) E/2
(2) 2E
(3) 4E
(4) E/4
The terminal potential difference of a cell when short-circuited is (E = E.M.F. of the cell)
(1) E
(2) E/2
(3) Zero
(4) E/3
The potential difference in open circuit for a cell is 2.2 volts. When a 4-ohm resistor is connected between its two electrodes the potential difference becomes 2 volts. The internal resistance of the cell will be :
(1) 1 ohm
(2) 0.2 ohm
(3) 2.5 ohm
(4) 0.4 ohm
A cell whose e.m.f. is 2 V and internal resistance is 0.1 Ω, is connected with a resistance of 3.9 Ω. The voltage across the cell terminal will be :
(1) 0.50 V
(2) 1.90 V
(3) 1.95 V
(4) 2.00 V
A cell of internal resistance r is connected to an external resistance R. The current will be maximum in R, if
(1) R = r
(2) R < r
(3) R > r
(4) None of these
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. |
Consider the circuit given here with the following parameters E.M.F. of the cell = 12 V. Internal resistance of the cell = 2 Ω. Resistance R = 4 Ω. Which one of the following statements is true.
(1) Rate of energy loss in the source is = 8 W
(2) Rate of energy conversion in the source is 16 W
(3) Power output in R is = 8 W
(4) Potential drop across R is = 16 V