An NPN transistor conducts when:
1. | both the collector and the emitter are positive with respect to the base. |
2. | the collector is positive and the emitter is negative with respect to the base. |
3. | the collector is positive and the emitter is at same potential as the base. |
4. | both the collector and the emitter are negative with respect to the base. |
A \(2\) V battery is connected across the points \(A\) and \(B\) as shown in the figure given below. Assuming that the resistance of each diode is zero in forward bias and infinity in reverse bias, the current supplied by the battery when its positive terminal is connected to \(A\) is:
1. | \(0.2\) A | 2. | \(0.4\) A |
3. | zero | 4. | \(0.1\) A |
In the circuit given below, if \(V(t)\) is the sinusoidal voltage source, then the voltage drop \(V_{AB}(t)\) across the resistance \(R\):
1. | is half-wave rectified. |
2. | is full-wave rectified. |
3. | has the same peak value in the positive and negative half-cycles. |
4. | has different peak values during the positive and negative half-cycles. |
1. \(0\) V
In a given circuit as shown the two input waveforms \(A\) and \(B\) are applied simultaneously. The resultant waveform \(Y\) is:
1. | 2. | ||
3. | 4. |
In a common emitter circuit, if VCC is changed by 0.2 V, collector current changes by 4 x 10–3 mA. The output resistance will be:
1. 10 k
2. 30 k
3. 50 k
4. 70 k
If the reverse bias in a junction diode is changed from \(5\) V to \(15\) V then the value of current changes from \(38~\mu \text{A}\) to \(88~\mu \text{A}\). The resistance of junction diode will be:
1. \(4\times10^{5}\)
2. \(3\times10^{5}\)
3. \(2\times10^{5}\)
4. \(10^{6}\)
In a transistor, a change of 8.0 mA in the emitter current produces a change of 7.8 mA in the collector current. What change in the base current is necessary to produce the same change in the collector current?
1. 50 A
2. 100 A
3. 150 A
4. 200 A
In a transistor circuit shown here, the base current is
1. 128.5 k
2. 257 k
3. 380.05 k
4. None of these
The logic behind the 'NOR' gate is that it gives:
1. | High output when both the inputs are low. |
2. | Low output when both the inputs are low. |
3. | High output when both the inputs are high. |
4. | None of these |