# Logic Gates

## Trending Questions

**Q.**The correct Boolean operation represented by the circuit diagram drawn is

- AND
- OR
- NAND
- NOR

**Q.**Find the current through the middle branch of the unbalanced Wheatstone's bridge circuit, as shown in figure.

- 0.460 A
- 0.023 A
- 0.1 A
- 0.046 A

**Q.**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 a 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-

- 300 Ω
- 50 Ω
- 100 Ω
- 200 Ω

**Q.**

Which of the following is the universal gate?

OR

NOT

AND

NAND

**Q.**If power dissipated in the 9 Ω resistor in the circuit shown in 36 W, the potential difference across the 2 Ω resistor is

- 8 Volt
- 4 Volt
- 2 Volt
- 10 Volt

**Q.**

Which of the following is not a network topology

bus

ring

star

connect

**Q.**

The following logic gate is equivalent to:

NOR Gate

AND Gate

OR Gate

NAND Gate

**Q.**The combination of the gate shown below produces

- AND gate
- NAND gate
- NOR gate
- OR gate

**Q.**In the combination of the following gates, the output Y can be written in terms of inputs A and B as

- ¯¯¯¯¯¯¯¯A.B
- A¯¯¯¯¯.B+¯¯¯A.B
- ¯¯¯¯¯¯¯¯A.B+A.B
- ¯¯¯¯¯¯¯¯¯¯¯A+B

**Q.**

Which of the following is the universal gate?

OR gate

AND gate

NAND gate

NOT gate

**Q.**How many NAND gates are used in an OR gate?

- Four
- Two
- Three
- Five

**Q.**For the forward biased diode characteristics shown in the figure, the dynamic resistance at ID=3 mA will be ____ Ω.

**Q.**Which of the following is not equal to 1 in boolean algebra?

- A+1
- A.¯A
- A+¯A
- ¯¯¯¯¯¯¯¯¯¯¯A.A

**Q.**A closely wound solenoid of 2000 turns and area of cross-section 1.5×10–4 m2 carries a current of 2.0 A. It is suspended through its centre and perpendicular to its length, allowing it to turn in a horizontal plane in a uniform magnetic field 5×10–2 tesla making an angle of 30∘ with the axis of the solenoid. The torque on the solenoid will be

- 1.5×10−3 Nm
- 3×10−2 Nm
- 3×10−3 Nm
- 1.5×10−2 Nm

**Q.**

The NOR gate is OR gate followed by

AND gate

OR gate

NOT gate

None of the above

**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

- 0, 0
- 0, 1
- 1, 0
- 1, 1

**Q.**Which of the following gates will have an output of 1?

- (a) and (b)
- (b) and (c)
- (c) and (d)
- (d) and (a)

**Q.**The combination of ‘NAND’ gates shown here under (figure) are equivalent to –

- An OR gate and an AND gate respectively
- An AND gate and a NOT gate respectively
- An AND gate and an OR gate respectively
- An OR gate and a NOT gate respectively

**Q.**In the circuit as shown in the figure, the heat produced by 6 Ω resistance due to current flowing in it is 60 calorie per second. The heat generated across 3 Ω resistance per second will be

- 60 cal/s
- 30 cal/s
- 120 cal/s
- 100 cal/s

**Q.**

Can A Diode Act As A Switch

**Q.**

The logic circuit shown below is equivalent to :

**Q.**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 :

**Q.**The truth table for the circuit given in the figure is :

- ⎡⎢ ⎢ ⎢ ⎢ ⎢ ⎢⎣ABY001011100110⎤⎥ ⎥ ⎥ ⎥ ⎥ ⎥⎦
- ⎡⎢ ⎢ ⎢ ⎢ ⎢ ⎢⎣ABY001010100110⎤⎥ ⎥ ⎥ ⎥ ⎥ ⎥⎦
- ⎡⎢ ⎢ ⎢ ⎢ ⎢ ⎢⎣ABY001011101111⎤⎥ ⎥ ⎥ ⎥ ⎥ ⎥⎦
- ⎡⎢ ⎢ ⎢ ⎢ ⎢ ⎢⎣ABY000010101111⎤⎥ ⎥ ⎥ ⎥ ⎥ ⎥⎦

**Q.**Two headlights on a car are wired in_______

- Series
- Parallel
- Series or parallel, we cannot say
- parallel in some car & in series in other car

**Q.**The output Y of the gate shown in the figure will be represented by :

- Y=A⋅B
- Y=A+B
- Y=¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯A+B
- Y=A¯¯¯¯B+B¯¯¯¯A

**Q.**

How many transistors are in $A3NAND$ gate?

**Q.**

The Boolean equation for the circuit given in the figure:

Y=¯A.B+C

Y=¯A.(¯B+¯C)

Y=¯A(B+C)

Y=¯A.(B+¯C)

**Q.**

The truth table for system of four NAND gates as shown in the figure is

ABY000010101111

ABY001011100110

ABY001010100111

ABY000011101110

**Q.**The logic circuit shown below has the input waveforms A and B as shown in the figure. Pick the correct output waveform

**Q.**

A logic gate is an electronic circuit which

Makes logic decisions

Works binary algebra

Allows electrons flow only in one direction

Alternates between 0 and 1 values