A transistor is operated in a common emitter configuration at V_c =2 V such that a change in the base current from 100 $\mu A$ to 300 $\mu A$ produces a change in the collector current from 10 mA to 20mA. The current gain is:

1.  75

2.  100 

3.  25

4.  50

Which one of the following statements is false?

The device that can act as a complete electronic circuit is:

1. Junction diode

2. Integrated circuit

3. Junction transistor

4. Zener diode

A common emitter amplifier has a voltage gain of 50, an input impedance of 100 Ω and an output impedance of 200 Ω. The power gain of the amplifier is:

1. 500

2. 1000

3. 1250

4. 50

To get an output Y = 1 from the circuit shown below, the input must be:

1. A=0 B=1 C=0

2. A=0 B=0 C=1

3. A=1 B=0 C=1

4. A=1 B=0 C=0

The symbolic representation of four logic gates is as shown:

(i)		(ii)
(ii)		(iv)

The logic symbols for OR, NOT, and NAND gates are respectively:
1. (iii), (iv), (ii)
2. (iv), (i), (iii)
3. (iv), (ii), (i)
4. (i), (iii), (iv)

The voltage gain of an amplifier with 9% negative feedback is 10. The voltage gain without feedback will be:

1. 90

2. 10

3. 1.25

4. 100

A p-n photodiode is made of a material with a bandgap of 2.0 eV. The minimum frequency of the radiation that can be absorbed by the material is nearly:

1. $10\times {10}^{14}$ $\mathrm{Hz}$

2. $5\times {10}^{14}$ $\mathrm{Hz}$

3. $1\times {10}^{14}$ $\mathrm{Hz}$

4. $20\times {10}^{14}$ $\mathrm{Hz}$

The circuit is equivalent to: 
     

1. AND gate
2. NAND gate
3. NOR gate
4. OR gate