Electronics and Communication Book Back Practice Test

12th Standard Physics — Electronics and Communication: Book Back Online Practice Test

Pick how many questions you want and set a time limit, then start. You'll get your score at the end with the correct answer and an explanation for every question. Free, in Tamil and English — 14 questions available.

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The barrier potential of a silicon diode is approximately,

A.0.7 V B.0.3V C.2.0 V D.2.2V

If a small amount of antimony (Sb) is added to germanium crystal,

A.it becomes a p-type semiconductor B.the antimony becomes an acceptor atom C.there will be more free electrons than hole in the semiconductor D.its resistance is increased

In an unbiased p-n junction, the majority charge carriers (that is, holes) in the p-region diffuse into n-region because of

A.the potential difference across the p-n junction B.the higher hole concentration in p-region than that in n-region C.the attraction of free electrons of n-region D.All of the above

If a positive half-wave rectified voltage is fed to a load resistor, for which part of a cycle there will be current flow through the load?

A.\(0^{\circ}–90^{\circ}\) B.\(90^{\circ}–180^{\circ}\) C.\(0^{\circ}–180^{\circ}\) D.\(0^{\circ}–360^{\circ}\)

The zener diode is primarily used as

A.Rectifier B.Amplifier C.Oscillator D.Voltage regulator

The principle based on which a solar cell operates is

A.Diffusion B.Recombination C.Photovoltaic action D.Carrier flow

The light emitted in an LED is due to

A.Recombination of charge carriers B.Reflection of light due to lens action C.Amplification of light falling at the junction D.Large current capacity.

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?

A.(i) and (ii) only B.(ii) only C.(ii) and (iii) only D.(i) (ii) and (iii)

To obtain sustained oscillation in an oscillator,

A.Feedback should be positive B.Feedback factor must be unity C.Phase shift must be 0 or \(2\pi\) D.All the above

Q10

If the input to the NOT gate is A = 1011, its output is

A.0100 B.1000 C.1100 D.0011

Q11

The given electrical network is equivalent to

A logic gate network consisting of interconnected NAND or NOR gates.

A.AND gate B.OR gate C.NOR gate D.NOT gate

Q12

The output of the following circuit is 1 when the input ABC is

A combination of logic gates with three inputs labeled A, B, and C.

A.101 B.100 C.110 D.010

Q13

The variation of frequency of carrier wave with respect to the amplitude of the modulating signal is called

A.Amplitude modulation B.Frequency modulation C.Phase modulation D.Pulse width modulation

Q14

The frequency range of 3 MHz to 30 MHz is used for

A.Ground wave propagation B.Space wave propagation C.Sky wave propagation D.Satellite communication

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About this Electronics and Communication test

This free online practice test covers Electronics and Communication from the 12th Standard Physics (Samacheer Kalvi) syllabus. Choose the number of questions and an optional time limit, then answer and submit — everything is checked in your browser, with the correct answers and a worked explanation shown at the end. For the full solutions to every question in this set, see the solved MCQs page.

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