If in a \(\mathrm{p\text-n}\) 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 \(V\text-I\) characteristics of a semiconductor device. Which of the following statements is correct?
1. | It is a \(V\text-I\) characteristic of a solar cell where the point \(A\) represents open-circuit voltage and the point \(B\) represents short-circuit current. |
2. | It is for a solar cell and points \(A\) and \(B\) represents open-circuit voltage and current respectively. |
3. | It is for a photodiode and points \(A\) and \(B\) represents open-circuit voltage and current respectively. |
4. | It is for an LED and points \(A\) and \(B\) represents open-circuit voltage and short-circuit current respectively. |
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)
(2)
(3)
(4)
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 . Base current is changed by 40
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.
The voltage gain of the amplifier is
1. 2000
2. 3000
3. 4000
4. 1000
Symbolic representation of four logic gates
are shown as
(i)
(ii)
(iii)
(iv)
Pick out which ones are for AND, NAND and
NOT gates, respectively.
1. (iii), (ii)and (i)
2. (iii), (ii) and (iv)
3. (ii), (iv) and (iii)
4. (ii), (iii) and (iv)
If a small amount of antimony is added to germanium crystal
(1) the antimony becomes an acceptor atom
(2) there will be more free electrons than holes in the semiconductor
(3) its resistance is increased
(4) it becomes a p-type semiconductor