Question 1: Palette 1/209

JEE Mains 2026 MCQ

Two p-n junction diodes $D_1$ and $D_2$ are connected as shown in figure. $A$ and $B$ are input signals and $C$ is the output. The given circuit will function as a ________.

A

AND Gate

B

OR Gate

C

NOR Gate

D

NAND Gate

Question 2: Palette 2/209

JEE Mains 2026 MCQ

Assuming in forward bias condition there is a voltage drop of 0.7 V across a silicon diode, the current through diode $D_1$ in the circuit is $\_\_\_\_$ mA .

(Assume all diodes in the given circuit are identical)

A

17.6

B

18.8

C

20.15

D

11.7

Question 3: Palette 3/209

JEE Mains 2026 MCQ

$ \text { Identify the correct truth table of the given logic circuit. } $

A

$ \begin{array}{|c|c|c|} \hline \text { A } & \text { B } & \text { Y } \\ \hline \hline 0 & 0 & 0 \\ \hline \hline 0 & 1 & 0 \\ \hline 1 & 0 & 1 \\ \hline 1 & 1 & 0 \\ \hline \end{array} $

B

$ \begin{array}{|c|c|c|} \hline \text { A } & \text { B } & \text { Y } \\ \hline \hline 0 & 0 & 0 \\ \hline \hline 0 & 1 & 1 \\ \hline 1 & 0 & 1 \\ \hline 1 & 1 & 0 \\ \hline \end{array} $

C

$ \begin{array}{|c|c|c|} \hline \text { A } & \text { B } & \text { Y } \\ \hline \hline 0 & 0 & 1 \\ \hline \hline 0 & 1 & 1 \\ \hline \hline 1 & 0 & 1 \\ \hline \hline 1 & 1 & 0 \\ \hline \end{array} $

D

$ \begin{array}{|c|c|c|} \hline \text { A } & \text { B } & \text { Y } \\ \hline \hline 0 & 0 & 1 \\ \hline \hline 0 & 1 & 0 \\ \hline 1 & 0 & 1 \\ \hline 1 & 1 & 0 \\ \hline \end{array} $

Question 4: Palette 4/209

JEE Mains 2026 MCQ

$ \text { For the given logic gate circuit, which of the following is the correct truth table? } $

A

$ \begin{array}{c|c|c} n & m & z \\ \hline 0 & 0 & 1 \\ 0 & 1 & 1 \\ 1 & 1 & 0 \\ 1 & 0 & 0 \end{array} $

B

$ \begin{array}{c|c|c} n & m & z \\ \hline 0 & 0 & 1 \\ 0 & 1 & 0 \\ 1 & 1 & 1 \\ 1 & 0 & 0 \end{array} $

C

$ \begin{array}{c|c|c} n & m & z \\ \hline 0 & 0 & 0 \\ 0 & 1 & 1 \\ 1 & 1 & 0 \\ 1 & 0 & 1 \end{array} $

D

$ \begin{array}{c|c|c} n & m & z \\ \hline 0 & 0 & 1 \\ 0 & 1 & 0 \\ 1 & 1 & 0 \\ 1 & 0 & 0 \end{array} $

Question 5: Palette 5/209

JEE Mains 2026 MCQ

The following diagram shows a Zener diode as a voltage regulator. The Zener diode is rated at $V_z=5 \mathrm{~V}$ and the desired current in load is 5 mA . The unregulated voltage source can supply upto 25 V . Considering the Zener diode can withstand four times of the load current, the value of resistor $R_s$ (shown in circuit) should be $\_\_\_\_$ $\Omega$.

A

100

B

10

C

1000

D

4000

Question 6: Palette 6/209

JEE Mains 2026 MCQ

The correct truth table for the given input data of the following logic gate is :

A

Inputs				Output
A	B	C	D	Y
1	1	0	1	1
0	0	1	1	0
1	0	1	0	0
1	1	1	1	1

B

Inputs				Output
A	B	C	D	Y
1	1	0	1	0
0	0	1	1	1
1	0	1	0	1
1	1	1	1	1

C

Inputs				Output
A	B	C	D	Y
1	1	0	1	1
0	0	1	1	0
1	0	1	0	1
1	1	1	1	0

D

Inputs				Output
A	B	C	D	Y
1	1	0	1	0
0	0	1	1	0
1	0	1	0	1
1	1	1	1	1

Question 7: Palette 7/209

JEE Mains 2026 MCQ

Find the correct combination of $\mathrm{A}, \mathrm{B}, \mathrm{C}$ and D inputs which can cause the LED to glow.

A

1000

B

0011

C

0100

D

1101

Question 8: Palette 8/209

JEE Mains 2026 MCQ

The charge stored by the capacitor C in the given circuit in the steady state is __________ µC.

A

7.5

B

5

C

10

D

12.5

Question 9: Palette 9/209

JEE Mains 2026 MCQ

$ \text { The given circuit works as : } $

A

NOR gate

B

OR gate

C

AND gate

D

NAND gate

Question 10: Palette 10/209

JEE Mains 2026 MCQ

$ \text { The output } Y \text { for the given inputs } A \text { and } B \text { to the circuit is : } $

A

B

C

D

Question 11: Palette 11/209

JEE Mains 2026 MCQ

Refer to the logic circuit given below. For two inputs ( $A=1, B=1$ ) and ( $A=0, B=1$ ), output ( Y ) will be $\_\_\_\_$ .

A

1, 0 respectively

B

0, 1 respectively

C

0, 0 respectively

D

1, 1 respectively

Question 12: Palette 12/209

JEE Mains 2026 MCQ

The maximum rated power of the LED is 2 mW and it is used in the circuit with input voltage of 5 V as shown in the figure below. The current through resistance $R_S$ is 0.5 mA .

The minimum value of the resistance of $R_S$, to ensure that the LED is not damaged is $\_\_\_\_$ $\mathrm{k} \Omega$.

A

6

B

2

C

4

D

5

Question 13: Palette 13/209

JEE Mains 2026 MCQ

In a semiconductor $p$-n diode, the doping concentrations on $p$-side and $n$-side are $10^{15}$ atoms $/ \mathrm{cm}^3$ and $10^{18}$ atoms $/ \mathrm{cm}^3$, respectively. Which one of the following statements is true?

A

Widths of depletion region on either side of the interface are equal

B

The depletion region width is more on p -side compared to that in n -side

C

The depletion region width is more on $n$-side compared to that in $p$-side

D

No depletion region forms because of unequal doping concentrations on p and n -sides

Question 14: Palette 14/209

JEE Mains 2026 MCQ

For the given logic circuit, which of the following inputs combination will make both LED-1 and LED-2 to glow?

A

$ \mathrm{A}=0, \mathrm{~B}=1, \mathrm{C}=1 $

B

$ \mathrm{A}=1, \mathrm{~B}=0, \mathrm{C}=0 $

C

$ \mathrm{A}=1, \mathrm{~B}=0, \mathrm{C}=1 $

D

$ \mathrm{A}=1, \mathrm{~B}=1, \mathrm{C}=0 $

Question 15: Palette 15/209

JEE Mains 2026 MCQ

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason $\mathbf{R}$

Assertion A : A diode under reverse-biased condition provides very small current which is nearly independent of voltage until a critical limit at which the current increases drastically.

Reason R : Below the critical voltage limit, only majority charge carriers flow which increases drastically above critical voltage.

choose the correct answer from the options given below

A

Both $\mathbf{A}$ and $\mathbf{R}$ are true and $\mathbf{R}$ is the correct explanation of $\mathbf{A}$

B

Both $\mathbf{A}$ and $\mathbf{R}$ are true but $\mathbf{R}$ is NOT the correct explanation of $\mathbf{A}$

C

A is true but $\mathbf{R}$ is false

D

A is false but $\mathbf{R}$ is true

Question 16: Palette 16/209

JEE Mains 2026 MCQ

Two 4 bits binary numbers, $A=1101$ and $B=1010$ are given in the inputs of a logic circuit shown in figure below. The output $(Y)$ will be :

A

$ Y=1101 $

B

$ Y=0010 $

C

$ Y=0111 $

D

$ Y=1000 $

Question 17: Palette 17/209

JEE Mains 2026 MCQ

Consider a circuit consisting of a capacitor $(20 \mu \mathrm{~F})$, resistor $(100 \Omega)$ and two identical diodes as shown in figure. The resistance of diode under forward biasing condition is $10 \Omega$. The time constant of the circuit is $\alpha \times 10^{-3} \mathrm{~s}$. The value of $\alpha$ is $\_\_\_\_$

A

2.2

B

2.0

C

2.1

D

2.4

Question 18: Palette 18/209

JEE Mains 2026 MCQ

If X and Y are the inputs, the given circuit works as _________.

A

OR gate

B

AND gate

C

NAND gate

D

NOR gate

Question 19: Palette 19/209

JEE Mains 2026 MCQ

For the given circuit (shown in part (A)) the time dependent input voltage $v_{in}(t)$ and corresponding output $v_{o}(t)$ are shown in part (B) and part (C), respectively. Identify the components that are used in the circuit between points X and Y.

A

B

C

D

Question 20: Palette 20/209

JEE Mains 2025 MCQ

The output voltage in the following circuit is (Consider ideal diode case)

A

0 V

B

+5 V

C

−5 V

D

10 V

Question 21: Palette 21/209

JEE Mains 2025 MCQ

Consider the following logic circuit.

The output is Y = 0 when :

A

A = 1 and B = 0

B

A = 0 and B = 0

C

A = 1 and B = 1

D

A = 0 and B = 1

Question 22: Palette 22/209

JEE Mains 2025 MCQ

In the following circuit, the reading of the ammeter will be

$($ Take Zener breakdown voltage $=4 \mathrm{~V})$

A

60 mA

B

80 mA

C

10 mA

D

24 mA

Question 23: Palette 23/209

JEE Mains 2025 MCQ

Consider a n-type semiconductor in which $\mathrm{n}_{\mathrm{e}}$ and $\mathrm{n}_{\mathrm{h}}$ are number of electrons and holes, respectively.

(A) Holes are minority carriers

(B) The dopant is a pentavalent atom

(C) $\mathrm{n}_{\mathrm{e}} \mathrm{n}_{\mathrm{h}} \neq \mathrm{n}_i^2$

(where $\mathrm{n}_i$ is number of electrons or holes in semiconductor when it is intrinsic form)

(D) $\mathrm{n}_{\mathrm{e}} \mathrm{n}_{\mathrm{h}} \geqslant \mathrm{n}_i^2$

(E) The holes are not generated due to the donors

Choose the correct answer from the options given below :

A

(A), (B), (E) only

B

(A), (C), (E) only

C

(A), (B), (C) only

D

(A), (C), (D) only

Question 24: Palette 24/209

JEE Mains 2025 MCQ

The Boolean expression $\mathrm{Y}=A \bar{B} C+\bar{A} \bar{C}$ can be realised with which of the following gate configurations.

A. One 3-input AND gate, 3 NOT gates and one 2-input OR gate, One 2-input AND gate,

B. One 3 -input AND gate, 1 NOT gate, One 2 -input NOR gate and one 2 -input OR gate

C. 3 -input OR gate, 3 NOT gates and one 2 -input AND gate

Choose the correct answer from the options given below:

A

B, C Only

B

A, B, C Only

C

A, B Only

D

A, C Only

Question 25: Palette 25/209

JEE Mains 2025 MCQ

$ \text {The truth table corresponding to the circuit given below is: } $

A

$ \begin{array}{|c|c|c|} \hline \mathrm{A} & \mathrm{~B} & \mathrm{C} \\ \hline 0 & 0 & 0 \\ \hline 0 & 1 & 0 \\ \hline 1 & 0 & 1 \\ \hline 1 & 1 & 1 \\ \hline \end{array} $

B

$ \begin{array}{|c|c|c|} \hline \text { A } & \mathrm{B} & \mathrm{C} \\ \hline 0 & 0 & 1 \\ \hline 1 & 0 & 0 \\ \hline 0 & 1 & 0 \\ \hline 1 & 1 & 0 \\ \hline \end{array} $

C

$ \begin{array}{|c|c|c|} \hline \text { A } & \mathrm{B} & \mathrm{C} \\ \hline 0 & 0 & 1 \\ \hline 0 & 1 & 0 \\ \hline 1 & 0 & 0 \\ \hline 1 & 1 & 0 \\ \hline \end{array} $

D

$ \begin{array}{|c|c|c|} \hline \mathrm{A} & \mathrm{~B} & \mathrm{C} \\ \hline 0 & 0 & 0 \\ \hline 1 & 0 & 0 \\ \hline 0 & 1 & 0 \\ \hline 1 & 1 & 1 \\ \hline \end{array} $

Question 26: Palette 26/209

JEE Mains 2025 MCQ

$ \text { Choose the correct logic circuit for the given truth table having inputs } A \text { and } B \text {. } $

Inputs		Output
A	B	Y
0	0	0
0	1	0
1	0	1
1	1	1

A

B

C

D

Question 27: Palette 27/209

JEE Mains 2025 MCQ

$ \text { In the digital circuit shown in the figure, for the given inputs the } P \text { and } Q \text { values are : } $

A

$P=0, Q=1$

B

$P=1, Q=0$

C

$\mathrm{P}=0, \mathrm{Q}=0$

D

$P=1, Q=1$

Question 28: Palette 28/209

JEE Mains 2025 MCQ

A zener diode with 5 V zener voltage is used to regulate an unregulated dc voltage input of 25 V . For a $400 \Omega$ resistor connected in series, the zener current is found to be 4 times load current. The load current $\left(I_L\right)$ and load resistance $\left(R_L\right)$ are :

A

$\mathrm{I}_{\mathrm{L}}=0.02 \mathrm{~mA} ; \mathrm{R}_{\mathrm{L}}=250 \Omega$

B

$\mathrm{I}_{\mathrm{L}}=10 \mathrm{~A} ; \mathrm{R}_{\mathrm{L}}=0.5 \Omega$

C

$\mathrm{I}_{\mathrm{L}}=10 \mathrm{~mA} ; \mathrm{R}_{\mathrm{L}}=500 \Omega$

D

$\mathrm{I}_{\mathrm{L}}=20 \mathrm{~mA} ; \mathrm{R}_{\mathrm{L}}=250 \Omega$

Question 29: Palette 29/209

JEE Mains 2025 MCQ

The truth table for the circuit given below is:

A

A	B	Y
0	0	0
1	1	1
1	0	1
0	1	1

B

A	B	Y
0	0	0
1	0	1
0	1	0
1	1	0

C

A	B	Y
0	0	0
1	0	0
1	1	0
0	1	1

D

A	B	Y
0	0	0
0	1	1
1	0	1
1	1	0

Question 30: Palette 30/209

JEE Mains 2025 MCQ

For the circuit shown above, equivalent GATE is :

A

NOT gate

B

NAND gate

C

AND gate

D

OR gate

Question 31: Palette 31/209

JEE Mains 2025 MCQ

Which of the following circuits has the same output as that of the given circuit?

A

B

C

D

Question 32: Palette 32/209

JEE Mains 2025 MCQ

The output of the circuit is low (zero) for :

(A) $X=0, Y=0$

(B) $X=0, Y=1$

(C) $X=1, Y=0$

(D) $X=1, Y=1$

Choose the correct answer from the options given below :

A

(A), (B) and (C) only

B

(A), (C) and (D) only

C

(B), (C) and (D) only

D

(A), (B) and (D) only

Question 33: Palette 33/209

JEE Mains 2025 MCQ

Consider the following statements :

A. The junction area of solar cell is made very narrow compared to a photo diode.

B. Solar cells are not connected with any external bias.

C. LED is made of lightly doped p-n junction.

D. Increase of forward current results in continuous increase of LED light intensity.

E. LEDs have to be connected in forward bias for emission of light.

Choose the correct answer from the options given below :

A

A, C, E Only

B

B, E Only

C

A, C Only

D

B, D, E Only

Question 34: Palette 34/209

JEE Mains 2025 MCQ

What is the current through the battery in the circuit shown below?

A

1.5 A

B

0.25 A

C

1.0 A

D

0.5 A

Question 35: Palette 35/209

JEE Mains 2025 MCQ

Refer to the circuit diagram given in the figure. which of the following observations are correct?

A. Total resistance of circuit is $6 \Omega$

B. Current in Ammeter is 1 A

C. Potential across $A B$ is 4 Volts.

D. Potential across CD is 4 Volts

E. Total resistance of the circuit is $8 \Omega$.

Choose the correct answer from the options given below:

A

B, C and E Only

B

A, C and D Only

C

A, B and C Only

D

A, B and D Only

Question 36: Palette 36/209

JEE Mains 2025 MCQ

To obtain the given truth table, following logic gate should be placed at G :

A

NOR Gate

B

OR Gate

C

AND Gate

D

NAND Gate

Question 37: Palette 37/209

JEE Mains 2025 MCQ

Which of the following circuits represents a forward biased diode?

Choose the correct answer from the options given below:

A

(C) and (E) only

B

(A) and (D) only

C

(B), (D) and (E) only

D

(B), (C) and (E) only

Question 38: Palette 38/209

JEE Mains 2024 MCQ

In the truth table of the above circuit the value of X and Y are :

A

1, 1

B

0, 1

C

1, 0

D

0, 0

Question 39: Palette 39/209

JEE Mains 2024 MCQ

The $I$-$V$ characteristics of an electronic device shown in the figure. The device is :

A

a solar cell

B

a transistor which can be used as an amplifier

C

a diode which can be used as a rectifier

D

a zener diode which can be used as a voltage regulator

Question 40: Palette 40/209

JEE Mains 2024 MCQ

A light emitting diode (LED) is fabricated using GaAs semiconducting material whose band gap is $1.42 \mathrm{~eV}$. The wavelength of light emitted from the LED is :

A

1243 nm

B

875 nm

C

650 nm

D

1400 nm

Question 41: Palette 41/209

JEE Mains 2024 MCQ

The output $\mathrm{Y}$ of following circuit for given inputs is :

A

$A \cdot B$

B

$\bar{A} \cdot B$

C

$\Lambda \cdot B(\Lambda+B)$

D

0

Question 42: Palette 42/209

JEE Mains 2024 MCQ

The acceptor level of a p-type semiconductor is $6 \mathrm{~eV}$. The maximum wavelength of light which can create a hole would be : Given $\mathrm{hc}=1242 \mathrm{~eV} \mathrm{~nm}$.

A

407 nm

B

103.5 nm

C

414 nm

D

207 nm

Question 43: Palette 43/209

JEE Mains 2024 MCQ

The correct truth table for the following logic circuit is :

A

B

C

D

Question 44: Palette 44/209

JEE Mains 2024 MCQ

The output (Y) of logic circuit given below is 0 only when :

A

$\mathrm{A}=0, \mathrm{~B}=0$

B

$\mathrm{A}=0, \mathrm{~B}=1$

C

$\mathrm{A}=1, \mathrm{~B}=0$

D

$\mathrm{A=1, B=1}$

Question 45: Palette 45/209

JEE Mains 2024 MCQ

Following gates section is connected in a complete suitable circuit.

For which of the following combination, bulb will glow (ON) :

A

$\mathrm{A}=1, \mathrm{~B}=1, \mathrm{C}=1, \mathrm{D}=0$

B

$\mathrm{A}=1, \mathrm{~B}=0, \mathrm{C}=0, \mathrm{D}=0$

C

$\mathrm{A}=0, \mathrm{~B}=0, \mathrm{C}=0, \mathrm{D}=1$

D

$\mathrm{A}=0, \mathrm{~B}=1, \mathrm{C}=1, \mathrm{D}=1$

Question 46: Palette 46/209

JEE Mains 2024 MCQ

Which of the diode circuit shows correct biasing used for the measurement of dynamic resistance of p-n junction diode :

A

B

C

D

Question 47: Palette 47/209

JEE Mains 2024 MCQ

Identify the logic gate given in the circuit :

A

OR gate

B

NAND gate

C

NOR gate

D

AND gate

Question 48: Palette 48/209

JEE Mains 2024 MCQ

The value of net resistance of the network as shown in the given figure is :

A

$(30 / 11) \Omega$

B

$6 \Omega$

C

$(5 / 2) \Omega$

D

$(15 / 4) \Omega$

Question 49: Palette 49/209

JEE Mains 2024 MCQ

To measure the temperature coefficient of resistivity $\alpha$ of a semiconductor, an electrical arrangement shown in the figure is prepared. The arm BC is made up of the semiconductor. The experiment is being conducted at $25^{\circ} \mathrm{C}$ and resistance of the semiconductor arm is $3 \mathrm{~m} \Omega$. Arm $\mathrm{BC}$ is cooled at a constant rate of $2^{\circ} \mathrm{C} / \mathrm{s}$. If the galvanometer $\mathrm{G}$ shows no deflection after $10 \mathrm{~s}$, then $\alpha$ is :

A

$-1 \times 10^{-2}{ }^{\circ} \mathrm{C}^{-1}$

B

$-2 \times 10^{-2}{ }^{\circ} \mathrm{C}^{-1}$

C

$-2.5 \times 10^{-2}{ }^{\circ} \mathrm{C}^{-1}$

D

$-1.5 \times 10^{-2}{ }^{\circ} \mathrm{C}^{-1}$

Question 50: Palette 50/209

JEE Mains 2024 MCQ

In the given circuit if the power rating of Zener diode is $10 \mathrm{~mW}$, the value of series resistance $R_s$ to regulate the input unregulated supply is :

A

$10 \mathrm{k} \Omega$

B

$10 \Omega$

C

$1 \mathrm{k} \Omega$

D

$ \frac{3}{7} \mathrm{k} \Omega<\mathrm{R}_{\mathrm{s}}<\frac{3}{5} \mathrm{k} \Omega$

Question 51: Palette 51/209

JEE Mains 2024 MCQ

The output of the given circuit diagram is -

A

B

C

D

Question 52: Palette 52/209

JEE Mains 2024 MCQ

Identify the logic operation performed by the given circuit.

A

AND

B

NOR

C

OR

D

NAND

Question 53: Palette 53/209

JEE Mains 2024 MCQ

In the given circuit, the voltage across load resistance (R$_L$) is :

A

8.75 V

B

9.00 V

C

8.50 V

D

14.00 V

Question 54: Palette 54/209

JEE Mains 2024 MCQ

A Zener diode of breakdown voltage $10 \mathrm{~V}$ is used as a voltage regulator as shown in the figure. The current through the Zener diode is :

A

0

B

30 mA

C

20 mA

D

50 mA

Question 55: Palette 55/209

JEE Mains 2024 MCQ

The truth table for this given circuit is :

A

B

C

D

Question 56: Palette 56/209

JEE Mains 2024 MCQ

In the given circuit, the breakdown voltage of the Zener diode is $3.0 \mathrm{~V}$. What is the value of $\mathrm{I}_{\mathrm{z}}$ ?

A

3.3 mA

B

10 mA

C

5.5 mA

D

7 mA

Question 57: Palette 57/209

JEE Mains 2024 MCQ

The truth table of the given circuit diagram is :

A

B

C

D

Question 58: Palette 58/209

JEE Mains 2024 MCQ

Which of the following circuits is reverse - biased?

A

B

C

D

Question 59: Palette 59/209

JEE Mains 2023 MCQ

In the given circuit, the current (I) through the battery will be

A

1A

B

$2.5 \mathrm{~A}$

C

$2 \mathrm{~A}$

D

$1.5 \mathrm{~A}$

Question 60: Palette 60/209

JEE Mains 2023 MCQ

The output from NAND gate having inputs A and B given below will be,

A

B

C

D

Question 61: Palette 61/209

JEE Mains 2023 MCQ

For the following circuit and given inputs A and B, choose the correct option for output '$Y$'

A

B

C

D

Question 62: Palette 62/209

JEE Mains 2023 MCQ

In an n-p-n common emitter (CE) transistor the collector current changes from 5 $\mathrm{mA}$ to $16 \mathrm{~mA}$ for the change in base current from $100~ \mu \mathrm{A}$ and $200 ~\mu \mathrm{A}$, respectively. The current gain of transistor is __________.

A

210

B

0.9

C

9

D

110

Question 63: Palette 63/209

JEE Mains 2023 MCQ

The logic operations performed by the given digital circuit is equivalent to:

A

NOR

B

AND

C

NAND

D

OR

Question 64: Palette 64/209

JEE Mains 2023 MCQ

The logic performed by the circuit shown in figure is equivalent to :

A

NAND

B

AND

C

OR

D

NOR

Question 65: Palette 65/209

JEE Mains 2023 MCQ

If each diode has a forward bias resistance of $25 ~\Omega$ in the below circuit,

Which of the following options is correct :

A

$\frac{I_{3}}{I_{4}}=1$

B

$\frac{\mathrm{I}_{1}}{\mathrm{I}_{2}}=2$

C

$\frac{I_{2}}{\mathrm{I}_{3}}=1$

D

$\frac{I_{1}}{I_{2}}=1$

Question 66: Palette 66/209

JEE Mains 2023 MCQ

A zener diode of power rating 1.6 W is to be used as voltage regulator. If the zener diode has a breakdown of 8V and it has to regulate voltage fluctuating between 3 V and 10 V. The value of resistance R_s for safe operation of diode will be

A

13 $\Omega$

B

13.3 $\Omega$

C

10 $\Omega$

D

12 $\Omega$

Question 67: Palette 67/209

JEE Mains 2023 MCQ

For a given transistor amplifier circuit in $\mathrm{CE}$ configuration $\mathrm{V}_{\mathrm{CC}}=1 \mathrm{~V}, \mathrm{R}_{\mathrm{C}}=1 ~\mathrm{k} \Omega, \mathrm{R}_{\mathrm{b}}=100 ~\mathrm{k} \Omega$ and $\beta=100$. Value of base current $\mathrm{I}_{\mathrm{b}}$ is

A

$\mathrm{I}_{\mathrm{b}}=100 ~\mu \mathrm{A}$

B

$\mathrm{I}_{\mathrm{b}}=0.1 ~\mu \mathrm{A}$

C

$\mathrm{I}_{\mathrm{b}}=1.0 ~\mu \mathrm{A}$

D

$\mathrm{I}_{\mathrm{b}}=10 ~\mu \mathrm{A}$

Question 68: Palette 68/209

JEE Mains 2023 MCQ

For the logic circuit shown, the output waveform at $\mathrm{Y}$ is:

A

B

C

D

Question 69: Palette 69/209

JEE Mains 2023 MCQ

Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R

Assertion A: Diffusion current in a p-n junction is greater than the drift current in magnitude if the junction is forward biased.

Reason R: Diffusion current in a p-n junction is from the $\mathrm{n}$-side to the p-side if the junction is forward biased.

In the light of the above statements, choose the most appropriate answer from the options given below

A

Both A and R are correct but R is NOT the correct explanation of A

B

A is correct but R is not correct

C

A is not correct but R is correct

D

Both A and R are correct and R is the correct explanation of A

Question 70: Palette 70/209

JEE Mains 2023 MCQ

Name the logic gate equivalent to the diagram attached

A

NOR

B

NAND

C

AND

D

OR

Question 71: Palette 71/209

JEE Mains 2023 MCQ

The resistivity $(\rho)$ of semiconductor varies with temperature. Which of the following curve represents the correct behaviour :

A

B

C

D

Question 72: Palette 72/209

JEE Mains 2023 MCQ

Choose the correct statement about Zener diode :

A

It works as a voltage regulator in reverse bias and behaves like simple pn junction diode in forward bias.

B

It works as a voltage regulator in both forward and reverse bias.

C

It works as a voltage regulator only in forward bias.

D

It works as a voltage regulator in forward bias and behaves like simple pn junction diode in reverse bias.

Question 73: Palette 73/209

JEE Mains 2023 MCQ

Match List I with List II:

	List I		List II
A.	Intrinsic semiconductor	I.	Fermi-level near the valence bond
B.	n-type semiconductor	II.	Fermi-level in the middle of valence and conduction band.
C.	p-type semiconductor	III.	Fermi-level near the conduction band
D.	Metals	IV.	Fermi-level inside the conduction band

Choose the correct answer from the options given below :

A

A-III, B-I, C-II, D-IV

B

A-II, B-I, C-III, D-IV

C

A-I, B-II, C-III, D-IV

D

A-II, B-III, C-I, D-IV

Question 74: Palette 74/209

JEE Mains 2023 MCQ

Given below are two statements :

Statement I: In a typical transistor, all three regions emitter, base and collector have same doping level.

Statement II: In a transistor, collector is the thickest and base is the thinnest segment.

In the light of the above statements, choose the most appropriate answer from the options given below.

A

Statement I is correct but Statement II is incorrect

B

Both Statement I and Statement II are incorrect

C

Statement I is incorrect but Statement II is correct

D

Both Statement I and Statement II are correct

Question 75: Palette 75/209

JEE Mains 2023 MCQ

The effect of increase in temperature on the number of electrons in conduction band ($\mathrm{n_e}$) and resistance of a semiconductor will be as:

A

$\mathrm{n}_{\mathrm{e}}$ decreases, resistance increases

B

Both $\mathrm{n}_{\mathrm{e}}$ and resistance increase

C

$\mathrm{n}_{\mathrm{e}}$ increases, resistance decreases

D

Both $\mathrm{n}_{\mathrm{e}}$ and resistance decrease

Question 76: Palette 76/209

JEE Mains 2023 MCQ

The output $Y$ for the inputs $A$ and $B$ of circuit is given by

Truth table of the shown circuit is:

A

B

C

D

Question 77: Palette 77/209

JEE Mains 2023 MCQ

The output waveform of the given logical circuit for the following inputs A and B as shown below, is :

A

B

C

D

Question 78: Palette 78/209

JEE Mains 2023 MCQ

For the given logic gates combination, the correct truth table will be

A

B

C

D

Question 79: Palette 79/209

JEE Mains 2023 MCQ

Which one of the following statement is not correct in the case of light emitting diodes?

A. It is a heavily doped p-n junction.

B. It emits light only when it is forward biased.

C. It emits light only when it is reverse biased.

D. The energy of the light emitted is equal to or slightly less than the energy gap of the semiconductor used.

Choose the correct answer from the options given below:

A

A

B

B

C

C and D

D

C

Question 80: Palette 80/209

JEE Mains 2023 MCQ

Statement I : When a Si sample is doped with Boron, it becomes P type and when doped by Arsenic it becomes N-type semi conductor such that P-type has excess holes and N-type has excess electrons.

Statement II : When such P-type and N-type semi-conductors, are fused to make a junction, a current will automatically flow which can be detected with an externally connected ameter.

In the light of above statements, choose the most appropriate answer from the options given below

A

Statement I is incorrect but statement II is correct

B

Both Statement I and statement II are correct

C

Statement I is correct but statement II is incorrect

D

Both Statement I and Statement II are incorrect

Question 81: Palette 81/209

JEE Mains 2023 MCQ

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Photodiodes are used in forward bias usually for measuring the light intensity.

Reason R : For a p-n junction diode, at applied voltage V the current in the forward bias is more than the current in the reverse bias for $\mathrm{|{V_z}| > \pm v \ge |{v_0}|}$ where $\mathrm{v_0}$ is the threshold voltage and $\mathrm{V_z}$ is the breakdown voltage.

In the light of the above statements, choose the correct answer from the options given below

A

Both A and R are true but R is NOT the correct explanation of A

B

A is true but R is false

C

Both A and R are true and R is the correct explanation of A

D

A is false but R is true

Question 82: Palette 82/209

JEE Mains 2023 MCQ

The logic gate equivalent to the given circuit diagram is :

A

NOR

B

OR

C

NAND

D

AND

Question 83: Palette 83/209

JEE Mains 2023 MCQ

Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R

Assertion A : Photodiodes are preferably operated in reverse bias condition for light intensity measurement.

Reason R : The current in the forward bias is more than the current in the reverse bias for a $p-n$ junction diode.

In the light of the above statements, choose the correct answer from the options given below :

A

Both A and R are true and R is the correct explanation of A

B

A is false but R is true

C

A is true but R is false

D

Both A and R are true but R is NOT the correct explanation of A

Question 84: Palette 84/209

JEE Mains 2022 MCQ

An n.p.n transistor with current gain $\beta=100$ in common emitter configuration is shown in figure. The output voltage of the amplifier will be

A

0.1 V

B

1.0 V

C

10 V

D

100 V

Question 85: Palette 85/209

JEE Mains 2022 MCQ

Identify the solar cell characteristics from the following options :

A

B

C

D

Question 86: Palette 86/209

JEE Mains 2022 MCQ

For a constant collector-emitter voltage of $8 \mathrm{~V}$, the collector current of a transistor reached to the value of $6 \mathrm{~mA}$ from $4 \mathrm{~mA}$, whereas base current changed from $20 \,\mu \mathrm{A}$ to $25 \,\mu \mathrm{A}$ value. If transistor is in active state, small signal current gain (current amplification factor) will be :

A

240

B

400

C

0.0025

D

200

Question 87: Palette 87/209

JEE Mains 2022 MCQ

A logic gate circuit has two inputs A and B and output Y. The voltage waveforms of A, B and Y are shown below.

The logic gate circuit is :

A

AND gate

B

OR gate

C

NOR gate

D

NAND gate

Question 88: Palette 88/209

JEE Mains 2022 MCQ

In the circuit, the logical value of $A=1$ or $B=1$ when potential at $A$ or $B$ is $5 \mathrm{~V}$ and the logical value of $A=0$ or $B=0$ when potential at $A$ or $B$ is $0 \mathrm{~V}$.

The truth table of the given circuit will be :

A

$\matrix{ A & B & Y \cr 0 & 0 & 0 \cr 1 & 0 & 0 \cr 0 & 1 & 0 \cr 1 & 1 & 1 \cr } $

B

$\matrix{ A & B & Y \cr 0 & 0 & 0 \cr 1 & 0 & 1 \cr 0 & 1 & 1 \cr 1 & 1 & 1 \cr } $

C

$\matrix{ A & B & Y \cr 0 & 0 & 0 \cr 1 & 0 & 0 \cr 0 & 1 & 0 \cr 1 & 1 & 0 \cr } $

D

$\matrix{ A & B & Y \cr 0 & 0 & 1 \cr 1 & 0 & 1 \cr 0 & 1 & 1 \cr 1 & 1 & 0 \cr } $

Question 89: Palette 89/209

JEE Mains 2022 MCQ

In the given circuit the input voltage V_in is shown in figure. The cut-in voltage of p-n junction diode (D₁ or D₂) is 0.6 V. Which of the following output voltage (V₀) waveform across the diode is correct?

A

B

C

D

Question 90: Palette 90/209

JEE Mains 2022 MCQ

In the following circuit, the correct relation between output (Y) and inputs A and B will be :

A

Y = AB

B

Y = A + B

C

$Y = \overline {AB} $

D

$Y = \overline {A+B} $

Question 91: Palette 91/209

JEE Mains 2022 MCQ

For using a multimeter to identify diode from electrical components, choose the correct statement out of the following about the diode :

A

It is two terminal device which conducts current in both directions.

B

It is two terminal device which conducts current in one direction only.

C

It does not conduct current gives an initial deflection which decays to zero.

D

It is three terminal device which conducts current in one direction only between central terminal and either of the remaining two terminals

Question 92: Palette 92/209

JEE Mains 2022 MCQ

Given below are two statements : One is labelled as Assertion A and the other is labelled as Reason R.

Assertion A : n-p-n transistor permits more current than a p-n-p transistor.

Reason R : Electrons have greater mobility as a charge carrier.

Choose the correct answer from the options given below :

A

Both A and R are true, and R is correct explanation of A.

B

Both A and R are true but R is NOT the correct explanation of A.

C

A is true but R is false.

D

A is false but R is true.

Question 93: Palette 93/209

JEE Mains 2022 MCQ

For a transistor to act as a switch, it must be operated in

A

Active region.

B

Saturation state only.

C

Cut-off state only.

D

Saturation and cut-off state.

Question 94: Palette 94/209

JEE Mains 2022 MCQ

Identify the correct Logic Gate for the following output (Y) of two inputs A and B.

A

B

C

D

Question 95: Palette 95/209

JEE Mains 2022 MCQ

The positive feedback is required by an amplifier to act an oscillator. The feedback here means :

A

External input is necessary to sustain ac signal in output.

B

A portion of the output power is returned back to the input.

C

Feedback can be achieved by LR network.

D

The base-collector junction must be forward biased.

Question 96: Palette 96/209

JEE Mains 2022 MCQ

The I-V characteristics of a p-n junction diode in forward bias is shown in the figure. The ratio of dynamic resistance, corresponding to forward bias voltage of 2 V and 4 V respectively, is :

A

1 : 2

B

5 : 1

C

1 : 40

D

20 : 1

Question 97: Palette 97/209

JEE Mains 2022 MCQ

Identify the logic operation performed by the given circuit:

A

AND gate

B

OR gate

C

NOR gate

D

NAND gate

Question 98: Palette 98/209

JEE Mains 2022 MCQ

The photodiode is used to detect the optical signals. These diodes are preferably operated in reverse biased mode because :

A

fractional change in majority carriers produce higher forward bias current

B

fractional change in majority carriers produce higher reverse bias current

C

fractional change in minority carriers produce higher forward bias current

D

fractional change in minority carriers produce higher reverse bias current

Question 99: Palette 99/209

JEE Mains 2021 MCQ

In the given figure, each diode has a forward bias resistance of 30$\Omega$ and infinite resistance in reverse bias. The current I₁ will be :

A

3.75 A

B

2.35 A

C

2 A

D

2.73 A

Question 100: Palette 100/209

JEE Mains 2021 MCQ

If V_A and V_B are the input voltages (either 5V or 0V) and V₀ is the output voltage then the two gates represented in the following circuit (A) and (B) are :-

A

AND and OR Gate

B

OR and NOT Gate

C

NAND and NOR Gate

D

AND and NOT Gate

Question 101: Palette 101/209

JEE Mains 2021 MCQ

Statement - I :

To get a steady dc output from the pulsating voltage received from a full wave rectifier we can connect a capacitor across the output parallel to the load R_L.

Statement - II :

To get a steady dc output from the pulsating voltage received from a full wave rectifier we can connect an inductor in series with R_L.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Statement I is true but Statement II is false

B

Statement I is false but Statement II is true

C

Both Statement I and Statement II are false

D

Both Statement I and Statement II are true

Question 102: Palette 102/209

JEE Mains 2021 MCQ

In the following logic circuit the sequence of the inputs A, B are (0, 0), (0, 1), (1, 0) and (1, 1). The output Y for this sequence will be :

A

1, 0, 1, 0

B

0, 1, 0, 1

C

1, 1, 1, 0

D

0, 0, 1, 1

Question 103: Palette 103/209

JEE Mains 2021 MCQ

Choose the correct waveform that can represent the voltage across R of the following circuit, assuming the diode is ideal one :

A

B

C

D

Question 104: Palette 104/209

JEE Mains 2021 MCQ

For a transistor $\alpha$ and $\beta$ are given as $\alpha = {{{I_C}} \over {{I_E}}}$ and $\beta = {{{I_C}} \over {{I_B}}}$. Then the correct relation between $\alpha$ and $\beta$ will be :

A

$\alpha = {{1 - \beta } \over \beta }$

B

$\beta = {\alpha \over {1 - \alpha }}$

C

$\alpha \beta = 1$

D

$\alpha = {\beta \over {1 - \beta }}$

Question 105: Palette 105/209

JEE Mains 2021 MCQ

For a transistor in CE mode to be used as an amplifier, it must be operated in :

A

Both cut-off and Saturation

B

Saturation region only

C

Cut-off region only

D

The active region only

Question 106: Palette 106/209

JEE Mains 2021 MCQ

Four NOR gates are connected as shown in figure. The truth table for the given figure is :

A

B

C

D

Question 107: Palette 107/209

JEE Mains 2021 MCQ

Identify the logic operation carried out by the given circuit :-

A

OR

B

AND

C

NOR

D

NAND

Question 108: Palette 108/209

JEE Mains 2021 MCQ

Statement I : By doping silicon semiconductor with pentavalent material, the electrons density increases.

Statement II : The n-type semiconductor has net negative charge.

In the light of the above statements, choose the most appropriate answer from the options given below :

A

Statement - I is true but Statement - II is false.

B

Statement - I is false but Statement - II is true.

C

Both Statement I and Statement II are true.

D

Both Statement I and Statement II are false.

Question 109: Palette 109/209

JEE Mains 2021 MCQ

Find the truth table for the function Y of A and B represented in the following figure.

A

B

C

D

Question 110: Palette 110/209

JEE Mains 2021 MCQ

Identify the logic operation carried out.

A

OR

B

AND

C

NOR

D

NAND

Question 111: Palette 111/209

JEE Mains 2021 MCQ

Consider a situation in which reserve biased current of a particular P-N junction increases when it is exposed to a light of wavelength $\le$ 621 nm. During this process, enhancement in carrier concentration takes place due to generation of hole-electron pairs. The value of band gap is nearly.

A

1 eV

B

4 eV

C

0.5 eV

D

2 eV

Question 112: Palette 112/209

JEE Mains 2021 MCQ

For the circuit shown below, calculate the value of I_z :

A

25 mA

B

0.1 A

C

0.15 A

D

0.05 A

Question 113: Palette 113/209

JEE Mains 2021 MCQ

The correct relation between $\alpha$ (ratio of collector current to emitter current) and $\beta$ (ratio of collector current to base current) of a transistor is :

A

$\beta = {\alpha \over {1 + \alpha }}$

B

$\alpha = {\beta \over {1 - \alpha }}$

C

$\alpha = {\beta \over {1 + \beta }}$

D

$\beta = {1 \over {1 - \alpha }}$

Question 114: Palette 114/209

JEE Mains 2021 MCQ

Which one of the following will be the output of the given circuit?

A

XOR Gate

B

NOR Gate

C

NAND Gate

D

AND Gate

Question 115: Palette 115/209

JEE Mains 2021 MCQ

The output of the given combination gates represents :

A

AND Gate

B

NOR Gate

C

NAND Gate

D

XOR Gate

Question 116: Palette 116/209

JEE Mains 2021 MCQ

The following logic gate is equivalent to :

A

NOR Gate

B

NAND Gate

C

OR Gate

D

AND Gate

Question 117: Palette 117/209

JEE Mains 2021 MCQ

Draw the output signal Y in the given combination of gates.

A

B

C

D

Question 118: Palette 118/209

JEE Mains 2021 MCQ

LED is constructed from Ga-As-P semiconducting material. The energy gap of this LED is 1.9 eV. Calculate the wavelength of light emitted and its colour.

[h = 6.63 $\times$ 10^$-$34 Js and c = 3 $\times$ 10⁸ ms^$-$1]

A

654 nm and orange colour

B

654 nm and red colour

C

1046 nm and red colour

D

1046 nm and blue colour

Question 119: Palette 119/209

JEE Mains 2021 MCQ

For extrinsic semiconductors; when doping level is increased;

A

Fermi-level of both p-type and n-type semiconductors will go upward for T > T_FK and downward for T < T_FK, where T_F is Fermi temperature.

B

Fermi-level of p-type semiconductor will go upward and Fermi-level of n-type semiconductors will go downward

C

Fermi-level of p and n-type semiconductors will not be affected.

D

Fermi-level of p-type semiconductors will go downward and Fermi-level of n-type semiconductor will go upward.

Question 120: Palette 120/209

JEE Mains 2021 MCQ

The truth table for the following logic circuit is :

A

B

C

D

Question 121: Palette 121/209

JEE Mains 2021 MCQ

A 5V battery is connected across the points X and Y. Assume D₁ and D₂ to be normal silicon diodes. Find the current supplied by the battery if the +ve terminal of the battery is connected to point X.

A

$ \sim $ 0.5 A

B

$ \sim $ 1.5 A

C

$ \sim $ 0.43 A

D

$ \sim $ 0.86 A

Question 122: Palette 122/209

JEE Mains 2021 MCQ

The logic circuit shown above is equivalent to :

A

B

C

D

Question 123: Palette 123/209

JEE Mains 2021 MCQ

Given below are two statements :

Statement I : PN junction diodes can be used to function as transistor, simply by connecting two diodes, back to back, which acts as the base terminal.

Statement II : In the study of transistor, the amplification factor $\beta$ indicates ratio of the collector current to the base current.

In the light of the above statements, choose the correct answer from the options given below.

A

Both Statement I and Statement II are false

B

Statement I is false but Statement II is true

C

Both Statement I and Statement II are true

D

Statement I is true but Statement II is false

Question 124: Palette 124/209

JEE Mains 2021 MCQ

Zener breakdown occurs in a p $-$ n junction having p and n both :

A

heavily doped and have wide depletion layer.

B

lightly doped and have narrow depletion layer.

C

heavily doped and have narrow depletion layer.

D

lightly doped and have wide depletion layer.

Question 125: Palette 125/209

JEE Mains 2021 MCQ

If an emitter current is changed by 4 mA, the collector current changes by 3.5 mA. The value of $\beta$ will be :

A

0.875

B

0.5

C

3.5

D

7

Question 126: Palette 126/209

JEE Mains 2020 MCQ

Identify the correct output signal Y in the given combination of gates (as shown) for the given inputs A and B.

A

B

C

D

Question 127: Palette 127/209

JEE Mains 2020 MCQ

Two Zener diodes (A and B) having breakdown voltages of 6 V and 4 V respectively, are connected as shown in the circuit below. The output voltage V₀ variation with input voltage linearly increasing with time, is given by :
(V_input = 0 V at t = 0)
(figures are qualitative)

A

B

C

D

Question 128: Palette 128/209

JEE Mains 2020 MCQ

With increasing biasing voltage of a photodiode, the photocurrent magnitude :

A

Increases initially and after attaining certain value, it decreases

B

Increases linearly

C

Increases initially and saturates finally

D

Remains constant

Question 129: Palette 129/209

JEE Mains 2020 MCQ

Identify the operation performed by the circuit given below :

A

AND

B

NAND

C

OR

D

NOT

Question 130: Palette 130/209

JEE Mains 2020 MCQ

Take the breakdown voltage of the
zener diode used in the given circuit as 6V.
For the input voltage shown in figure below,
the time variation of the output voltage is:
(Graphs drawn are schematic and not to scale)

A

B

C

D

Question 131: Palette 131/209

JEE Mains 2020 MCQ

If a semiconductor photodiode can detect a photon with a maximum wavelength of 400 nm, then its band gap energy is :

Planck’s constant h = 6.63 $ \times $ 10^–34 J.s. Speed of light c = 3 $ \times $ 10⁸ m/s

A

1.5 eV

B

2.0 eV

C

3.1 eV

D

1.1 eV

Question 132: Palette 132/209

JEE Mains 2020 MCQ

Which of the following will NOT be observed when a multimeter (operating in resistance measuring mode) probes connected across a component, are just reversed?

A

Multimeter shows NO deflection in both cases i.e. before and after reversing the probes if the chosen component is metal wire.

B

Multimeter shows a deflection, accompanied by a splash of light out of connected component in one direction and NO deflection on reversing the probes if the chosen component is LED.

C

Multimeter shows an equal deflection in both cases i.e. before and after reversing the probes if the chosen component is resistor.

D

Multimeter shows NO deflection in both cases i.e. before and after reversing the probes if the chosen component is capacitor.

Question 133: Palette 133/209

JEE Mains 2020 MCQ

When a diode is forward biased, it has a voltage drop of 0.5 V. The safe limit of current through the diode is 10 mA. If a battery of emf 1.5 V is used in the circuit, the value of minimum resistance to be connected in series with the diode so that the current does not exceed the safe limit is

A

50 $\Omega $

B

200 $\Omega $

C

300 $\Omega $

D

100 $\Omega $

Question 134: Palette 134/209

JEE Mains 2020 MCQ

In the following digital circuit, what will be the output at ‘Z’, when the
input (A, B) are (1, 0), (0, 0), (1, 1,), (0, 1)

A

1, 1, 0, 1

B

0, 1, 0, 0

C

1, 0, 1, 1

D

0, 0, 1, 0

Question 135: Palette 135/209

JEE Mains 2020 MCQ

The current i in the network is :

A

0.6 A

B

0.3 A

C

0 A

D

0.2 A

Question 136: Palette 136/209

JEE Mains 2020 MCQ

Two identical capacitors A and B, charged to the same potential 5V are connected in two different circuits as shown below at time t = 0. If the charge on capacitors A and B at time t = CR is Q_A and Q_B respectively, then (Here e is the base of natural logarithm)

A

Q_A = ${{CV} \over e}$, Q_B = ${{VC} \over 2}$

B

Q_A = ${{CV} \over 2}$, Q_B = ${{VC} \over e}$

C

Q_A = VC, Q_B = ${{VC} \over e}$

D

Q_A = VC, Q_B = CV

Question 137: Palette 137/209

JEE Mains 2020 MCQ

In the given circuit, value of Y is :

A

toggles between 0 and 1

B

1

C

will not execute

D

0

Question 138: Palette 138/209

JEE Mains 2020 MCQ

Boolean relation at the output stage-Y for the following circuit is :

A

A.B

B

$\overline A + \overline B $

C

$\overline A .\overline B $

D

A + B

Question 139: Palette 139/209

JEE Mains 2020 MCQ

In the figure, potential difference between A and B is :

A

10 V

B

5 V

C

zero

D

15 V

Question 140: Palette 140/209

JEE Mains 2020 MCQ

Which of the following gives a reversible operation?

A

B

C

D

Question 141: Palette 141/209

JEE Mains 2019 MCQ

Figure shows a DC voltage regulator circuit, with a Zener diode of breakdown voltage = 6V. If the unregulated input voltage varies between 10 V to 16 V, then what is maximum Zener current?

A

3.5 mA

B

1.5 mA

C

2.5 mA

D

7.5 mA

Question 142: Palette 142/209

JEE Mains 2019 MCQ

The transfer characteristic curve of a transistor, having input and output resistance 100 $\Omega $ and 100 k$\Omega $ respectively is shown in the figure. The voltage and power gain, are respectively:

A

5 × 10⁴, 5 × 10⁵

B

5 × 10⁴, 5 × 10⁶

C

5 × 10⁴, 2.5 × 10⁶

D

2.5 × 10⁴, 2.5 × 10⁶

Question 143: Palette 143/209

JEE Mains 2019 MCQ

The truth table for the circuit given in the fig. is:

A

$\left| {\matrix{ A & B & Y \cr 0 & 0 & 1 \cr 0 & 1 & 1 \cr 1 & 0 & 1 \cr 1 & 1 & 1 \cr } } \right|$

B

$\left| {\matrix{ A & B & Y \cr 0 & 0 & 1 \cr 0 & 1 & 0 \cr 1 & 0 & 0 \cr 1 & 1 & 0 \cr } } \right|$

C

$\left| {\matrix{ A & B & Y \cr 0 & 0 & 1 \cr 0 & 1 & 1 \cr 1 & 0 & 0 \cr 1 & 1 & 0 \cr } } \right|$

D

$\left| {\matrix{ A & B & Y \cr 0 & 0 & 0 \cr 0 & 1 & 0 \cr 1 & 0 & 1 \cr 1 & 1 & 1 \cr } } \right|$

Question 144: Palette 144/209

JEE Mains 2019 MCQ

The figure represents a voltage regulator circuit using a Zener diode. The breakdown voltage of the Zener diode is 6 V and the load resistance is, R_L = 4k$\Omega $. The series resistance of the circuit is R_i = 1 k$\Omega $. If the battery voltage V_B varies from 8 V to 16 V, what are the minimum and maximum values of the current through Zener diode?

A

0.5 mA; 8.5 mA

B

1.5 mA; 8.5 mA

C

1 mA; 8.5 mA

D

0.5 mA; 6 mA

Question 145: Palette 145/209

JEE Mains 2019 MCQ

An n-p-n transistor operates as a common emitter amplifier, with a power gain of 60 dB. The input circuit resistance is 100$\Omega $ and the output load resistance is 10 k$\Omega $. The common emitter current gain $\beta $ is :

A

10⁴

B

10²

C

6 × 10²

D

60

Question 146: Palette 146/209

JEE Mains 2019 MCQ

The logic gate equivalent to the given logic circuit is :-

A

NAND

B

AND

C

NOR

D

OR

Question 147: Palette 147/209

JEE Mains 2019 MCQ

An NPN transistor is used in common emitter configuration as an amplifier with 1 k$\Omega $ load resistance. Signal voltage of 10 mV is applied across the base-emitter. This produces a 3 mA change in the collector current and 15μA change in the base current of the amplifier. The input resistance and voltage gain are :

A

0.67 kW, 200

B

0.33 kW, 1.5

C

0.67 kW, 300

D

0.33 kW, 300

Question 148: Palette 148/209

JEE Mains 2019 MCQ

A common emitter amplifier circuit, built using an npn transistor, is shown in the figure. Its dc current gain is 250, R_C = 1k$\Omega$ and V_CC = 10 V. What is the minimum base current for V_CE to reach saturation ?

A

100 $\mu $A

B

7 $\mu $A

C

10 $\mu $A

D

40 $\mu $A

Question 149: Palette 149/209

JEE Mains 2019 MCQ

The reverse breakdown voltage of a Zener diode is 5.6 V in the given circuit.

The current IZ through the Zener is :

A

7 mA

B

17 mA

C

15mA

D

10 mA

Question 150: Palette 150/209

JEE Mains 2019 MCQ

In the figure, given that V_BB supply can vary from 0 to 5.0 V, V_CC = 5V, $\beta $_dc = 200, R_B = 100 k$\Omega $, R_C = 1 k$\Omega $ and V_BE = 1.0 V. The minimum base current and the input voltage at which the transistor will go to saturation, will be respectively :

A

20 $\mu $A and 2.8 V

B

25 $\mu $A and 2.8 V

C

20 $\mu $A and 3.5 V

D

25 $\mu $A and 3.5 V

Question 151: Palette 151/209

JEE Mains 2019 MCQ

The output of the given logic circuit is :

A

$\overline A B$

B

$AB + \overline {AB} $

C

$A\overline B + \overline A B$

D

$A\overline B $

Question 152: Palette 152/209

JEE Mains 2019 MCQ

The circuit shown below contains two ideal diodes, each with a forward resistance of 50 $\Omega $. If the battery voltage is 6 V, the current through the 100 $\Omega $ resistance (in Amperes) is :

A

0.027

B

0.030

C

0.036

D

0.020

Question 153: Palette 153/209

JEE Mains 2019 MCQ

In the given circuit the current through Zener Diode is close to:

A

0.0 mA

B

6.7 mA

C

4.0 mA

D

6.0 mA

Question 154: Palette 154/209

JEE Mains 2019 MCQ

For the circuit shown below, the current through the Zener diode is -

A

5 mA

B

zero

C

14 mA

D

9 mA

Question 155: Palette 155/209

JEE Mains 2019 MCQ

To get output 1 at R, for the given logic gate circuit the input values must be

A

x = 0,  y = 0

B

x = 1,  y = 0

C

x = 0,  y = 1

D

x = 1,  y = 1

Question 156: Palette 156/209

JEE Mains 2019 MCQ

Ge and Si diodes start conducting at 0.3 V and 0.7 V respectively. In the following figure if Ge diode connection are reversed, the value of V₀ changes by : (assume that the Ge diode has large breakdown voltage)

A

0.8 V

B

0.6 V

C

0.2 V

D

0.4 V

Question 157: Palette 157/209

JEE Mains 2019 MCQ

Mobility of electrons in a semiconductor is defined as the ratio of their drift velocity to the applied electric field. If, for an n-type semiconductor, the density of electrons is 10¹⁹ m^$-$3 and their mobility is 1.6 m²/(V.s) then the resistivity of the semiconductor (since it is an n-type semiconductor contribution of holes is ignored) is close to :

A

$2\,\Omega $m

B

4$\,\Omega $m

C

0.4 $\,\Omega $m

D

0.2 $\,\Omega $m

Question 158: Palette 158/209

JEE Mains 2018 MCQ

In the given circuit, the current through zener diode is :

A

5.5 mA

B

6.7 mA

C

2.5 mA

D

3.3 mA

Question 159: Palette 159/209

JEE Mains 2018 MCQ

The reading of the ammeter for a silicon diode in the given circuit is :

A

13.5 mA

B

0

C

15 mA

D

11.5 mA

Question 160: Palette 160/209

JEE Mains 2018 MCQ

Truth table for the following digital circuit will be :

A

B

C

D

Question 161: Palette 161/209

JEE Mains 2018 MCQ

In a common emitter configuration with suitable bias, it is given that ${R_L}$ is the load resistance and ${R_{BE}}$ is small signal dynamic resistance (input side). Then, voltage gain, current gain and power gain are given, respectively, by :

$\beta $ is curret gain, ${{\rm I}_B},{{\rm I}_C}$ and ${{\rm I}_E}$ are respectively base, collector and emitter currents.

A

$\beta {{{R_L}} \over {{R_{BE}}}},{{\Delta {{\rm I}_C}} \over {\Delta {{\rm I}_B}}},{\beta ^2}{{{R_L}} \over {{R_{BE}}}}$

B

$\beta {{{R_L}} \over {{R_{BE}}}},{{\Delta {{\rm I}_E}} \over {\Delta {{\rm I}_B}}},{\beta ^2}{{{R_L}} \over {{R_{BE}}}}$

C

${\beta ^2}{{{R_L}} \over {{R_{BE}}}},{{\Delta {{\rm I}_C}} \over {\Delta {{\rm I}_E}}},{\beta ^2}{{{R_L}} \over {{R_{BE}}}}$

D

${\beta ^2}{{{R_L}} \over {{R_{BE}}}},{{\Delta {{\rm I}_C}} \over {\Delta {{\rm I}_B}}},\beta {{{R_L}} \over {{R_{BE}}}}$

Question 162: Palette 162/209

JEE Mains 2017 MCQ

The current gain of a common emitter amplifier is 69. If the emitter current is 7.0 mA, collector current is :

A

9.6 mA

B

6.9 mA

C

0.69 mA

D

69 mA

Question 163: Palette 163/209

JEE Mains 2017 MCQ

The V-I characteristic of a diode is shown in the figure. The ratio of forward to reverse bias resistance is :

A

10

B

10^$-$6

C

10⁶

D

100

Question 164: Palette 164/209

JEE Mains 2017 MCQ

What is the conductivity of a semiconductor sale having electron concentration of $5 \times {10^{18}}\,\,{m^{ - 3}},$ hole concentration of $5 \times {10^{19}}\,\,{m^{ - 3}},$ electron mobility of 2.0 m² V^$-$1 s^-1 and hole mobility of 0.01 m² V^$-$1 s^$-$1 ?

(Take charge of electronas 1.6 $ \times $ 10 ^$-$19 c)

A

1.68 ($\Omega $-m)^$-$1

B

1.83 ($\Omega $-m)^$-$1

C

0.59 ($\Omega $-m)^$-$1

D

1.20 ($\Omega $-m)^$-$1

Question 165: Palette 165/209

JEE Mains 2017 MCQ

In a common emitter amplifier circuit using an n-p-n transistor, the phase difference between the input and the output voltages will be:

A

180°

B

45°

C

90°

D

135°

Question 166: Palette 166/209

JEE Mains 2016 MCQ

To get an output of 1 from the circuit shown in figure the input must be :

A

a = 0, b = 1, c = 0

B

a = 1, b = 0, c = 0

C

a = 1, b = 0, c = 1

D

a = 0, b = 0, c = 1

Question 167: Palette 167/209

JEE Mains 2016 MCQ

The ratio (R) of output resistance r₀, and the input resistance ri in measurements of input and output characteristics of a transistor is typically in the range:

A

R ~ 10² $-$ 10³

B

R ~ 1 $-$ 10

C

R ~ 0.1 $-$ 0.01

D

R ~ 0.1 $-$ 1.0

Question 168: Palette 168/209

JEE Mains 2016 MCQ

A realistic graph depicting the variation of the reciprocal of input resistance in an input characteristics measurement in a commonemitter transistor configuration is :

A

B

C

D

Question 169: Palette 169/209

JEE Mains 2016 MCQ

An experiment is performed to determine the I - V characteristics of a Zener diode, which has a protective resistance of R = 100 $\Omega $, and a maximum power of dissipation rating of 1 W. The minimum voltage range of the DC source in the circuit is :

A

0 $-$ 5 V

B

0 $-$ 8 V

C

0 $-$ 12 V

D

0 $-$ 24 V

Question 170: Palette 170/209

JEE Mains 2016 MCQ

An unknown transistor needs to be identified as a npn or pnp type. A multimeter, with + ve and − ve terminals, is used to measure resistance between different terminals of transistor. If terminal 2 is the base of the transistor then which of the following is correct for a pnp transistor ?

A

+ ve termial 1, $-$ve terminal 2, resistance high

B

+ ve termial 2, $-$ve terminal 1, resistance high

C

+ ve termial 3, $-$ve terminal 2, resistance high

D

+ ve termial 2, $-$ve terminal 3, resistance low

Question 171: Palette 171/209

JEE Mains 2016 MCQ

The truth table given in fig. represents :

A	B	Y
0	0	0
0	1	1
1	0	1
1	1	1

A

AND - Gate

B

OR - Gate

C

NAND - Gate

D

NOR - Gate

Question 172: Palette 172/209

JEE Mains 2016 MCQ

The temperature dependence of resistance of $Cu$ and undoped $Si$ in the temperature range $300-400$ $K,$ is best described by :

A

Linear increases for $Cu,$ exponential decrease of $Si.$

B

Linear decrease for $Cu,$ linear decrease for $Si$

C

Linear increase for $Cu,$ linear increase for $Si.$

D

Linear increase for $Cu,$ exponential increase for $Si$

Question 173: Palette 173/209

JEE Mains 2016 MCQ

If $a, b, c, d$ are inputs to a gate and $x$ is its output, then, as per the following time graph, the gate is :

A

$OR$

B

$NAND$

C

$NOT$

D

$AND$

Question 174: Palette 174/209

JEE Mains 2016 MCQ

Identify the semiconductor devices whose characteristics are given below, in the order $(a), (b), (c), (d)$ :

A

Simple diode, Zener diode, Solar cell, Light dependent resistance

B

Zener diode, Simple diode, Light dependent resistance, Solar cell

C

Solar cell, Light dependent resistance, Zener diode, simple diode

D

Zener diode, Solar cell, simple diode, Light dependent resistance

Question 175: Palette 175/209

JEE Mains 2016 MSQ

For a common emitter configuration, if $\alpha $ and $\beta $ have their usual meanings, the incorrect relationship between $\alpha $ and $\beta $ is :

A

$\alpha = {\beta \over {1 + \beta }}$

B

$\alpha = {{{\beta ^2}} \over {1 + {\beta ^2}}}$

C

${1 \over \alpha } = {1 \over \beta } + 1$

D

$\alpha = {\beta \over {1 - {\beta ^2}}}$

Question 176: Palette 176/209

JEE Mains 2015 MCQ

A red $LED$ emits light at $0.1$ watt uniformly around it. The amplitude of the electric field of the light at a distance of $1$ $m$ from the diode is :

A

$5.48$ $V/m$

B

$7.75$ $V/m$

C

$1.73$ $V/m$

D

$2.45$ $V/m$

Question 177: Palette 177/209

JEE Mains 2014 MCQ

The forward biased diode connection is:

A

B

C

D

Question 178: Palette 178/209

JEE Mains 2014 MCQ

The current voltage relation of diode is given by ${\rm I} = \left( {{e^{100V/T}} - 1} \right)mA,$ where the applied voltage $V$ is in volts and the temperature $T$ is in degree kelvin. If a student makes an error measuring $ \pm 0.01\,V$ while measuring the current of $5$ $mA$ at $300$ $K,$ what will be the error in the value of current on $mA$?

A

$0.2$ $mA$

B

$0.02$ $mA$

C

$0.5$ $mA$

D

$0.05$ $mA$

Question 179: Palette 179/209

JEE Mains 2013 MCQ

The ${\rm I}$-$V$ characteristic of an $LED$ is

A

B

C

D

Question 180: Palette 180/209

JEE Mains 2013 MCQ

A diode detector is used to detect an amplitude modulated wave of $60\% $ modulation by using a condenser of capacity $250$ picofarad in parallel with a load resistance $100$ kilo $ohm.$ Find the maximum modulated frequency which could be detected by it.

A

$10.62$ $MHz$

B

$10.62$ $kHz$

C

$5.31$ $MHz$

D

$5.31$ $kHz$

Question 181: Palette 181/209

JEE Mains 2012 MCQ

Truth table for system of four $NAND$ gates as shown in figure is:

A

B

C

D

Question 182: Palette 182/209

JEE Mains 2010 MCQ

The combination of gates shown below yields

A

OR gate

B

NOT gate

C

XOR gate

D

NAND gate

Question 183: Palette 183/209

JEE Mains 2009 MCQ

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

Output is

A

B

C

D

Question 184: Palette 184/209

JEE Mains 2009 MCQ

A $p$-$n$ junction $(D)$ shown in the figure can act as a rectifier. An alternating current source $(V)$ is connected in the circuit.

The current $(I)$ in the resistor $(R)$ can be shown by :

A

B

C

D

Question 185: Palette 185/209

JEE Mains 2008 MCQ

In the circuit below, $A$ and $B$ represent two inputs and $C$ represents the output.

The circuit represents

A

NOR gate

B

AND gate

C

NAND gate

D

OR gate

Question 186: Palette 186/209

JEE Mains 2008 MCQ

A working transistor with its three legs marked $P,Q$ and $R$ is tested using a multi-meter. No conduction is found between $P$ and $Q$. By connecting the common (negative) terminal of the multi-meter to $R$ and the other (positive) terminal to $P$ or $Q,$ some resistance is seen on the multi-meter. Which of the following is true for the transistor?

A

It is an $npn$ transistor with $R$ as base

B

It is an $pnp$ transistor with $R$ as collector

C

It is an $pnp$ transistor with $R$ as emitter

D

It is an $npn$ transistor with $R$ as collector

Question 187: Palette 187/209

JEE Mains 2007 MCQ

If in a $p$-$n$ junction diode, a square input signal of $10$ $V$ is applied as shown

Then the output signal across ${R_L}$ will be

A

B

C

D

Question 188: Palette 188/209

JEE Mains 2007 MCQ

Carbon, silicon and germanium have four valence electrons each. At room temperature which one of the following statements is most appropriate ?

A

The number of free electrons for conduction is significant only in $Si$ and $Ge$ but small in $C.$

B

The number of free conduction electrons is significant in $C$ but small in $Si$ and $Ge.$

C

The number of free conduction electrons is negligibly small in all the three.

D

The number of free electrons for conduction is significant in all the three

Question 189: Palette 189/209

JEE Mains 2006 MCQ

If the lattice constant of this semiconductor is decreased, then which of the following is correct?

A

All ${E_c},{E_g},{E_v}$ increase

B

${E_c}$ and ${E_v}$ increase, but ${E_g}$ decreases

C

${E_c}$ and ${E_v}$ decrease, but ${E_g}$ increases

D

All ${E_c},{E_g},{E_v}$ decrease

Question 190: Palette 190/209

JEE Mains 2006 MCQ

In the following, which one of the diodes is reverse biased?

A

B

C

D

Question 191: Palette 191/209

JEE Mains 2006 MCQ

The circuit has two oppositively connected ideal diodes in parallel. What is the current following in the circuit?

A

$1.71$ $A$

B

$2.00$ $A$

C

$2.31$ $A$

D

$1.33$ $A$

Question 192: Palette 192/209

JEE Mains 2006 MCQ

In a common base mode of a transistor, the collector current is $5.488$ $mA$ for an emitter current of $5.60mA.$ The value of the base current amplification factor $\left( \beta \right)$ will be

A

$49$

B

$50$

C

$51$

D

$48$

Question 193: Palette 193/209

JEE Mains 2006 MCQ

If the ratio of the concentration of electrons to that of holes in a semiconductor is ${7 \over 5}$ and the ratio of currents is ${7 \over 4},$ then what is the ratio of their drift velocities?

A

${5 \over 8}$

B

${4 \over 5}$

C

${5 \over 4}$

D

${4 \over 7}$

Question 194: Palette 194/209

JEE Mains 2006 MCQ

A solid which is not transparent to visible light and whose conductivity increases with temperature is formed by

A

Ionic bonding

B

Covalent bonding

C

Vander Waals bonding

D

Metallic bonding

Question 195: Palette 195/209

JEE Mains 2005 MCQ

In a full wave rectifier circuit operating from $50$ $Hz$ mains frequency, the fundamental frequency in the ripple would be

A

$25$ $Hz$

B

$50$ $Hz$

C

$70.7$ $Hz$

D

$100$ $Hz$

Question 196: Palette 196/209

JEE Mains 2005 MCQ

In a common base amplifier, the phase difference between the input signal voltage and output voltage is

A

$\pi $

B

${\pi \over 4}$

C

${\pi \over 2}$

D

$0$

Question 197: Palette 197/209

JEE Mains 2005 MCQ

The electrical conductivity of a semiconductor increases when electromagnetic radiation of wavelength shorter than $2480$ $nm$ is incident on it. The band gap in $(eV)$ for the semiconductor is

A

$2.5$ $eV$

B

$1.1$ $eV$

C

$0.7$ $eV$

D

$0.5$ $eV$

Question 198: Palette 198/209

JEE Mains 2004 MCQ

A piece of copper and another of germanium are cooled from room temperature to $77K,$ the resistance of

A

copper increases and germanium decreases

B

each of them decreases

C

each of them increases

D

copper decreases and germanium increases

Question 199: Palette 199/209

JEE Mains 2004 MCQ

The manifestation of band structure in solids is due to

A

Bohr's correspondence principle

B

Pauli's exclusion principle

C

Heisenberg's uncertainty principle

D

Boltzmann's law

Question 200: Palette 200/209

JEE Mains 2004 MCQ

When $p$-$n$ junction diode is forward biased then

A

both the depletion region and barrier height are reduced

B

the depletion region is widened and barrier height is reduced

C

the depletion region is reduced and barrier height is increased

D

both the depletion region and barrier height are increased

Question 201: Palette 201/209

JEE Mains 2004 MCQ

When $npn$ transistor is used as an amplifer

A

electrons move from collector to base

B

holes move from emitter to base

C

electrons move from base to collector

D

holes move from base to emitter

Question 202: Palette 202/209

JEE Mains 2004 MCQ

For a transistor amplifier in common emitter configuration for load impedance of $1k\,\Omega $ $\left( {{h_{fe}} = 50} \right.$ and $\left. {{h_{oe}} = 25} \right)$ the current gain is

A

$-24.8$

B

$-15.7$

C

$-5.2$

D

$-48.78$

Question 203: Palette 203/209

JEE Mains 2003 MCQ

The difference in the variation of resistance with temperature in a metal and a semiconductor arises essentially due to the difference in the

A

crystal structure

B

variation of the number of charge carries with temperature

C

type of bonding

D

variation of scattering mechanism with temperature

Question 204: Palette 204/209

JEE Mains 2003 MCQ

In the middle of the depletion layer of a reverse- biased $p$-$n$ junction, the

A

electric field is zero

B

potential is maximum

C

electric field is maximum

D

potential is zero

Question 205: Palette 205/209

JEE Mains 2003 MCQ

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

A

each of these decreases

B

copper strip increases and that of germanium decreases

C

copper strip decreases and that of germanium increases

D

each of these increases

Question 206: Palette 206/209

JEE Mains 2002 MCQ

By increasing the temperature, the specific resistance of a conductor and a semiconductor

A

increases for both

B

decreases for both

C

increases, decreases

D

decreases, increases

Question 207: Palette 207/209

JEE Mains 2002 MCQ

At absolute zero, Si acts as

A

non-metal

B

metal

C

insulator

D

none of these

Question 208: Palette 208/209

JEE Mains 2002 MCQ

The energy band gap is maximum in

A

metals

B

superconductors

C

insulator

D

semiconductor

Question 209: Palette 209/209

JEE Mains 2002 MCQ

The part of a transistor which is most heavily doped to produce large number of majority carriers is

A

emmiter

B

base

C

collector

D

can be any of the above three