\(12\) cells each having the same emf are connected in series with some cells wrongly connected. The arrangement is connected in series with an ammeter and two similar cells which are in series. Current is \(3~\text{A}\) when cells and battery aid each other and is \(2~\text{A}\) when cells and battery oppose each other. The number of cells wrongly connected is/are:
1. \(4\)
2. \(1\)
3. \(3\)
4. \(2\)
Variation of current passing through a conductor with the voltage applied across its ends varies is shown in the diagram below. If the resistance \((R)\) is determined at points \(A\), \(B\), \(C\) and \(D\), we will find that:
1. | \(R_C = R_D\) | 2. | \(R_B>R_A\) |
3. | \(R_C>R_B\) | 4. | None of these |
For a cell, the graph between the potential difference \((V)\) across the terminals of the cell and the current \((I)\) drawn from the cell is shown in the figure below. The emf and the internal resistance of the cell are, respectively:
1. | \(2~\text{V}, 0.5 ~\Omega\) | 2. | \(2~\text{V}, 0.4 ~\Omega\) |
3. | \(>2~\text{V}, 0.5 ~\Omega\) | 4. | \(>2~\text{V}, 0.4 ~\Omega\) |
A battery consists of a variable number \('n'\) of identical cells having internal resistances connected in series. The terminals of battery are short circuited and the current \(i\) is measured. The graph below that shows the relationship between \(i\) and \(n\) is:
1. | 2. | ||
3. | 4. |
A light bulb, a capacitor and a battery are connected together as shown below with the switch S initially open. When the switch S is closed, which one of the following is true?
1. The bulb will light up for an instant when
the capacitor starts charging.
2. The bulb will light up when
the capacitor is fully charged.
3. The bulb will not light up at all.
4. The bulb will light up and go off at regular intervals.
The effective resistance between points \(P\) and \(Q\) of the electrical circuit shown in the figure is:
1. | \(\frac{2 R r}{\left(R + r \right)}\) | 2. | \(\frac{8R\left(R + r\right)}{\left( 3 R + r\right)}\) |
3. | \(2r+4R\) | 4. | \(\frac{5R}{2}+2r\) |
What is the equivalent resistance between terminals \(A\) and \(B\) of the network?
1. | \(\dfrac{57}{7}~\Omega\) | 2. | \(8~\Omega\) |
3. | \(6~\Omega\) | 4. | \(\dfrac{57}{5}~\Omega\) |
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
In the circuit shown below, \(E_1 = 4.0~\text{V}\), \(R_1 = 2~\Omega\), \(E_2 = 6.0~\text{V}\), \(R_2 = 4~\Omega\) and \(R_3 = 2~\Omega\). The current \(I_1\) is:
1. \(1.6\) A
2. \(1.8\) A
3. \(1.25\) A
4. \(1.0\) A
In the circuit given below, the emf 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