A Zener diode is shown in the following circuit diagram. When the source voltage fluctuates such that \(V>V_z\) then:
1. | \(I_1, I_2~\text{and}~I_3\) change. | all the current
2. | \(I_1\) and \(I_2\) change and \(I_3\) remains constant. | only
3. | \(I_1\) and \(I_3\) change and \(I_2\) remains constant. | only
4. | all the currents remain constant. |
When the emitter current increases by 10 mA, the base current increases by 0.4 mA. The value of voltage gain in the common emitter configuration of the amplifier will be:
(output and input resistance ratio is 50)
1. 1200
2. 1250
3. 150
4. 120
If the current gain in the transistor is 50, then is equal to:
1. 2 V
2. 3 V
3. 4 V
4. 6 V
The net charges on -type semiconductor and -type semiconductor are, respectively:
1. | Positive, negative | 2. | Negative, positive |
3. | Positive, positive | 4. | Zero, zero |
1. | Forward biasing | 2. | Reverse biasing |
3. | No biasing | 4. | All of these |
1. \(2\) A and zero
2. \(3\) A and \(2\) A
3. \(2\) A and \(3\) A
4. zero and \(2\) A
If in a reverse-biased \(\mathrm{p\text-n}\) junction, an increase in carrier concentration takes place due to the creation of new hole-electron pairs by the light of wavelength less than or equal to \(620\) nm, then the bandgap is:
1. \(1\) eV
2. \(2\) eV
3. \(20\) eV
4. \(0.2\) eV
1. | 2. | ||
3. | 4. |
A n-p-n transistor operates in a common emitter mode as shown. The value of \(R_{L}\) is:
\(\small\left ( \text{Given,}I_{C}=4 mA,~V_{CE}=4~V,V_{BE}=0.6~V~\text{and}~\beta _{dc}=100 \right )\\\)
1. 1 k
2. 2 k
3. 3 k
4. 4 k
1. | It requires a low operational voltage. |
2. | It has a fast on-off switching capability. |
3. | The bandwidth of the emitted light is \(100\) A to \(10000\) A. |
4. | It does not require warm-up time. |