The given electrical network is equivalent to 

1. AND gate 

2. OR gate

3. NOR gate

4. NOT gate 

Which one of the following represents forward biased circuit?

1. 

2. 

3. 

4. 

What is the output Y in the following circuit, when all the three inputs A,B,C are first 0 and then 1 ?

1. 0,1

2. 0,0 

3. 1,0

4. 1,1

In the given figure, a diode D is connected to an external resistance R = 100 Ω  and an e.m.f of 3.5 V. If the barrier potential developed across the diode is 0.5 V, the current in the circuit will be


1. 30mA

2. 40mA

3. 20mA

4. 35mA

The barrier potential of a p-n junction depends on

(i)type of semiconductor material

(ii)amount of doping

(iii)temperature

Which one of the following is correct

1. (i) and (ii)only

2. (ii) only

3. (ii) and (iii)only

4. (i),(ii) and (iii)

In a CE transistor amplifier, the audio signal voltage across the collector resistance of 2 $k\Omega is 2V.$ If the base resistance is 1 $k\Omega$ and the current amplification of the transistor is 100, the input signal voltage is

1. 0.1 V                                         2. 1.0 V

3. 1mV                                         4. 10mV

C and Si both have same lattice structure,having 4 bonding electrons in each.However, C is insulator whereas Si is intrinsic semiconductor. This is because 

1. in case of C, the valence band is not completely filled at absolute zero temperature

2. in case of C,the condition band is partly filled even at absolute zero temperature 

3. the four bonding electrons in the case of C lie in the second orbit,Whereas in the case of Si they lie in the third

4 .the four bonding electrons in the case of C lie in the third orbit, whereas for Si they lie in the fourth orbit

The figure shows a logic circuit with two inputs A and B and the output C.The voltage wave forms across A, B and C are as given.The logic circuit gate is 

1. OR gate                                          2. NOR gate

3. AND gate                                        4. NAND gate

The input resistance of a silicon transistor is

100 $\mathrm{\Omega }$. Base current is changed by 40 $\mathrm{\mu A}$

which results in a change in collector current

by 2 mA. This transistor is used as a common-

emitter amplifier with a load resistance of 4 k$\mathrm{\Omega }$.

The voltage gain of the amplifier is

1. 2000

2. 3000

3. 4000

4. 1000

To get an output Y=1 in given circuit, which

of the following input will be correct ?

    A     B      C                  

1. 1     0       0             
2. 1     0      1
3. 1      1     0             
4. 0     1      0