What is the value of current \(I\) in the network shown below?
1. | \(2\) A | 2. | \(3\) A |
3. | \(4\) A | 4. | \(7\) A |
A current passes through a wire of variable cross-section in steady-state as shown. Then incorrect statement is:
1. | Current density increases in the direction of the current. |
2. | Potential increases in the direction of the current. |
3. | Electric field increases in the direction of the current. |
4. | Drift speed increases in the direction of the current. |
The value of E (emf of the cell) in the circuit given below is:
1. | 24 V | 2. | 32 V |
3. | 16 V | 4. | 8 V |
Two cells of emf \(E\) and internal resistance \(r_1\) and \(r_2\) are connected in series through an external resistance \(R\). The value of \(R\) for which the potential difference across one of the cells becomes zero will be:
1. | \(\dfrac{r_{1} r_{2}}{r_{1} + r_{2}}\) | 2. | \(r_{1} + r_{2}\) |
3. | \(|r_{1} - r_{2}|\) | 4. | \(\dfrac{r_{1}}{r_{2}}\) |
In the given circuit diagram, \(3\) identical bulbs are connected. If bulb \(B_3\) get fused suddenly, how will the brightness of bulbs \(B_1\) and \(B_2\) change?
1. | Brightness of bulb \(B_1\) will increase whereas brightness of bulb \(B_2\) will decrease |
2. | Brightness of bulb \(B_2\) will increase whereas brightness of bulb \(B_1\) will decrease |
3. | Brightness of both bulbs \(B_1\) and \(B_2\) will increase |
4. | Brightness of bulb \(B_1\) will increase whereas brightness of bulb \(B_2\) will remain the same |
What is the reading of the voltmeter of resistance \(1200~\Omega\) connected in the following circuit diagram?
1. | \(2.5\) V | 2. | \(5.0\) V |
3. | \(7.5\) V | 4. | \(40\) V |
The dependence of resistivity \((\rho)\) on the temperature \((T)\) of a semiconductor is, roughly, represented by:
1. | 2. | ||
3. | 4. |
Current through the \(2~\Omega\) resistance in the electrical network shown is:
1. | zero | 2. | \(1\) A |
3. | \(3\) A | 4. | \(5\) A |
A capacitor \(C\) is charged with the help of a resistance \(R\) as shown in the figure, Variation of \((V_{R}+V_{C})\) with time t is correctly shown in which of the options?
(\(V_{R}\) and \(V_{C}\) are instantaneous potential drops across \(R\) and \(C\) respectively).
1. | ![]() |
2. | ![]() |
3. | ![]() |
4. | ![]() |
Two batteries, one of emf \(18~\text{V}\) and internal resistance \(2~\Omega\) and the other of emf \(12\) V and internal resistance \(1~\Omega\), are connected as shown. Reading of the voltmeter is:
(if voltmeter is ideal)
1. \(14\) V
2. \(15\) V
3. \(18\) V
4. \(30\) V