To get output 1 for the following circuit, the correct choice for the input is

                       

(1) $A=1, B=0, C=0$       

(2) $A=1, B=1, C=0$

(3) $A=1, B=0, C=1$       

(4) $A=0, B=1, C=0$

An n-p-n transistor is connected in the common base configuration in a given amplifier. A load resistance of 800Ω is connected in the collector circuit and the voltage drop across it is 0.8 V. If the current amplification factor is 0.96 and the input resistance of the circuits is 192 Ω the voltage gain and the power gain of the amplifier will respectively be

1. 3.69,3.84
2. 4,4
3. 4,3.69
4. 4,3.84

If in a p-n junction, a square input signal of 10 V is applied as shown, then the output across R_L will be:
              

1.		2.
3.		4.

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 given graph represents the V-I characteristic for a semiconductor device. Which of the following statement is correct?

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)

The output (x) of logic circuit shown in figure will be 

(1) $X=\stackrel{=}{A}·\stackrel{=}{B}$

(2) $X=\overline{A.B}$

(3)$X=A·B$

(4)$X=\overline{A+B}$

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