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Semiconductor Electronics Materials Devices And Simple Circuits

Q: A circuit of logic gates given below, some input signal A, B, C are given with their output signal x, y and z is given in respective option, choose correct options :

From the figure we get options A, B, and D as correct.

Q: The logic circuit shown below has the input waveforms 'A' and 'B' as shown. Pick out the correct output waveform.

From the figure we can see the logic gate table of NOT and NOR gate\$A\$ \$NOT \ gate(X)\$1 00 10 11 01 00 10 1\$B\$ \$NOT \ gate(Y)\$1 00 11 00 11 00 11 0\$X\$ \$Y\$ \$NOR \ gate\$0 0 11 1 01 0 00 1 00 0 11 1 0 1 0 0

Q: A truth table is given below. Which of the following has this type of truth table ?A0101B0011Y1000

In NOR: \$\bar Y=\bar{A+B}\$i.e., \$\bar{0+0}=\bar{0}=1; \$\$\bar{1+0}=\bar{1}=0\$\$\bar{0+1}=\bar{1}=0;\$\$\bar{1+1}=0\$

Q: For the given combination of gates, if the logic states of inputs A, B, C are as follows \$A = B = C = 0\$ and \$A= B = 1, C = 0\$ then the logic states of output D are

The output D for the given combination:\$D=\bar{(A+B).C}=\bar{(A+B )}+C\$If \$A = B = C = 0\$ then \$D = (\bar{0+0})+\bar{0}=\bar{0}+\bar{0}=1+1=1\$if \$ = B = 1, C = 0\$ then \$D = (\bar{1+1})+\bar{0}=\bar{1}+\bar{0}=0+1=1\$

Q: A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of:

Copper is metallic conductor and germanium is semiconductor therefore as temperature decreases resistance of good conductor decreases while for semiconductor it increases.

Q: A Zener diode is connected to a battery and a load as shown. The currents \$I\$, \$I_Z\$ and \$I_L\$ are respectively

As long as the \$V_{in} \$ is greater than the zener Voltage \$10 V \$, the zener is in breakdown region and hence the voltage across the load remains constant. The series limiting resistance \$4k\Omega \$ limits the input current. Current in load \$I_L = \dfrac{10}{2 \times 10^3 } = 5mA \$Voltage drop across the \$4k\Omega\$ is \$60-10 = 50V \$ Hence \$ I = \dfrac{50}{4\times 10^3 } = 12.5 mA \$Hence, \$I_Z = I - I_L = 12.5 - 5 = 7.5 mA \$

Q: Which logic gate is represented by the following combination of logic gates:

\$Y=\overline {\overline {A}+\overline {B}}\$According to \$De\$ morgan's theorem \$Y=\overline {\overline {A}+\overline {B}}=\overline {\bar A . \bar B}=A.B\$

Q: Pure silicon crystal of length \$l (0.1m)\$ and area \$A\$(\$10^{-4}m^2\$) has the mobility of electrons (\$\mu_e\$) and holes (\$\mu_h\$) as \$0.135 m^2/Vs\$ and \$0.048 m^2/Vs\$ , respectively. If the voltage applied across it is \$2V\$ and the intrinsic charge concentration is \$n_i = 1.5 \times 10^6 m^{-3}\$, then the total current flowing through the crystal is

Given:\$l = 0.1m\$ \$A = 10^{-4} m^{-2}\$\$\mu_e = 0.135 m^2 (Vs)^{-1}\$\$\mu_h = 0.048 m^2 (Vs)^{-1}\$\$n_i = 1.5 \times 10^{6} m^{-3}\$\$E = 2 V\$The conductivity is:\$\sigma = n_i(\mu_e + \mu_h) e\$\$\sigma = 1.5 \times 10^{6} (0.135 + 0.048) 1.6 \times 10^{-19}\$\$\sigma = 1.5 (0.183) 1.6 \times 10^{-13}\$\$\sigma = 0.4392 \times 10^{-13} Sm^{-1}\$Now, the resistance is given by,\$R = \dfrac{l}{\sigma (A)}\$\$R = \dfrac{0.1}{0.4392 \times 10^{-13} (10^{-4})}\$\$R = 0.2276 \times 10^{17} \Omega\$Hence, the current is:\$I = \dfrac{V}{R} = \dfrac{2}{0.2276 \times 10^{17}}\$\$I = 8.787 \times 10^{-17} A\$

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JEE Mains JEE Advanced NEET AIIMS Easy Qs Med Qs Hard Qs

A circuit of logic gates given below, some input signal A, B, C are given with their output signal x, y and z is given in respective option, choose correct options :

A = 1, B = 1, C = 1

then

x = 0, y = 1, z = 1

A = 0, B = 0

and

C = 1

then

x = 1, y = 0, z = 1

A = 0, B = 0

and

C = 1

then

x = 1, y = 0, z = 0

If OR gate is replaced by NOR gate then net output signal of the circuit becomes

z = 0

for the input

A = 0, B = 0

and

C = 1

Hard

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The logic circuit shown below has the input waveforms 'A' and 'B' as shown. Pick out the correct output waveform.

Hard

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The following figure shows a logic gate circuit with two inputs A and B the output Y. The voltage waveforms of A, B and Y are as given-
The logic gate is-

OR gate

AND gate

NAND gate

NOR gate

Hard

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A truth table is given below. Which of the following has this type of truth table ?

A
0
1
0
1

B
0
0
1
1

Y
1
0
0
0

XOR gate

NOR gate

AND gate

OR gate

Hard

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Assertion

STATEMENT-1 : If output of a AND gate is fed to OR gate, it is called NOR gate.

Reason

STATEMENT-2 : If output of a AND gate is fed to NOT gate, it is called NAND gate.

Statement-1 is True, Statement-2 is True; Statement-2 is a correct explanation for Statement-1

Statement-1 is True, Statement-2 is True; Statement-2 is NOT a correct explanation for Statement-1

Statement-1 is True, Statement-2 is False.

Statement-1 is False, Statement-2 is True.

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For the given combination of gates, if the logic states of inputs A, B, C are as follows $A = B = C = 0$ and $A = B = 1, C = 0$ then the logic states of output D are

0, 0

0, 1

1, 0

1, 1

Hard

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A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of:

each of them increases

each of them decreases

copper increases and germanium decreases

copper decreases and germanium increases.

Hard

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A Zener diode is connected to a battery and a load as shown. The currents $I$ , $I_{Z}$ and $I_{L}$ are respectively

12.5 m A, 5 m A, 7.5 m A

15 m A, 7.5 m A, 7.5 m A

15 m A, 7.5 m A, 5 m A

12.5 m A, 7.5 m A, 5 m A

Hard

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Which logic gate is represented by the following combination of logic gates:

NAND

AND

NOR

Hard

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Pure silicon crystal of length $l (0.1 m)$ and area $A$ ( $1 0^{- 4} m^{2}$ ) has the mobility of electrons ( $μ_{e}$ ) and holes ( $μ_{h}$ ) as $0.135 m^{2} / V s$ and $0.048 m^{2} / V s$ , respectively. If the voltage applied across it is $2 V$ and the intrinsic charge concentration is $n_{i} = 1.5 \times 1 0^{6} m^{- 3}$ , then the total current flowing through the crystal is

8.78 \times 1 0^{- 17} A

6.25 \times 1 0^{- 17} A

7.89 \times 1 0^{- 17} A

2.456 \times 1 0^{- 17} A

Hard

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Semiconductor Electronics Materials Devices And Simple Circuits

Physics 2087 Views

A circuit of logic gates given below, some input signal A, B, C are given with their output signal x, y and z is given in respective option, choose correct options :

The logic circuit shown below has the input waveforms 'A' and 'B' as shown. Pick out the correct output waveform.

The following figure shows a logic gate circuit with two inputs A and B the output Y. The voltage waveforms of A, B and Y are as given- The logic gate is-

A truth table is given below. Which of the following has this type of truth table ? A 0 1 0 1 B 0 0 1 1 Y 1 0 0 0

STATEMENT-1 : If output of a AND gate is fed to OR gate, it is called NOR gate.

STATEMENT-2 : If output of a AND gate is fed to NOT gate, it is called NAND gate.

For the given combination of gates, if the logic states of inputs A, B, C are as follows A=B=C=0 and A=B=1,C=0 then the logic states of output D are

A piece of copper and another of germanium are cooled from room temperature to 80 K. The resistance of:

A Zener diode is connected to a battery and a load as shown. The currents I, IZ​ and IL​ are respectively

Which logic gate is represented by the following combination of logic gates:

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The following figure shows a logic gate circuit with two inputs A and B the output Y. The voltage waveforms of A, B and Y are as given-
The logic gate is-

A truth table is given below. Which of the following has this type of truth table ?

A
0
1
0
1

B
0
0
1
1

Y
1
0
0
0

For the given combination of gates, if the logic states of inputs A, B, C are as follows $A = B = C = 0$ and $A = B = 1, C = 0$ then the logic states of output D are

A Zener diode is connected to a battery and a load as shown. The currents $I$ , $I_{Z}$ and $I_{L}$ are respectively