Free Electronics MCQs with Answers
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A p-n junction forms when p-type and n-type semiconductor regions meet, creating a depletion layer, barrier potential and rectifying action. The work covers forward and reverse bias, junction current, diode characteristics, and how a diode converts alternating current into pulsating direct current through half-wave and full-wave rectification.
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Read the Electronics notesFree MDCAT chapter notes with key terms660 questions · page 19 of 33
361. In full wave rectifier with input frequency 50 Hz the ripple in the output is mainly of frequency:
- A. 25 Hz
- B. 50Hz
- C. 100 Hz
- D. Zero
Explanation: In full wave rectification ripple frequency is twice the input frequency.
Correct answer: 100 Hz- A. 7.07V
- B. 14.14V
- C. 16.8V
- D. 12V
Explanation: Option A: 7.07V: This option represents the RMS (Root Mean Square) voltage of 7.07V.
Correct answer: 14.14V- A. Half wave rectifier
- B. Full wave rectifier
- C. Both
- D. All
Explanation: Transistors can not act as rectifiers. They may, however, act as amplifiers.
Correct answer: All- A. 80.6 %
- B. 40.6 %
- C. 70%
- D. 50%
Explanation: The maximum theoretical efficiency of a half-wave rectifier is 40.6% or approximately 41%.In a half-wave rectifier, only half of the input…
Correct answer: 40.6 %- A. Negative plate
- B. Positive plate
- C. Positive deflection
- D. Pass through the medium
Explanation: Gamma rays have no charge, hence 0 deflections, but their high penetrating power allows them to simply pass through most mediums without…
Correct answer: Pass through the medium- A. Half wave
- B. Full wave
- C. Bridge
- D. All of the above options are correct
Explanation: Bridge rectifier is formed by connecting four diodes in the form of a Wheatstone bridge. It also provides full wave rectification.
Correct answer: Bridge- A. 1.21
- B. 0.8
- C. 0.6
- D. 0.4
Explanation: Ripple factor determines how well a half-wave rectifier can convert AC voltage to DC voltage.
Correct answer: 1.21- A. Oscillation
- B. Half wave rectification
- C. Full wave rectification
- D. None of these
Explanation: The principle behind the working of a cathode ray oscilloscope (CRO) is the use of a cathode ray tube (CRT) to display electrical signals…
Correct answer: None of these- A. 2
- B. 3
- C. 4
- D. 1
Explanation: A centre-tapped full-wave rectifier is a rectifier that uses a centre-tapped transformer to convert AC into DC.
Correct answer: 2- A. Negative plate
- B. Positive plate
- C. No deflection
- D. Pass through the medium
Explanation: Gamma rays have no charge, hence 0 deflections, but their high penetrating power allows them to simply pass through most mediums without…
Correct answer: Pass through the medium- A. Phase wave rectifier
- B. Full wave
- C. halfwave
- D. none of them
Explanation: A phase wave rectifier is not a recognized type of rectifier. The commonly known types of rectifiers are full wave rectifier and half wave…
Correct answer: Phase wave rectifier- A. 358.98 mW
- B. 275.2 mW
- C. 145.76 mW
- D. 456.78 mW
Explanation: The correct AC power input is calculated using the formula: A.c power input = Irms^2 (Rf + Rr).
Correct answer: 275.2 mW- A. 10√2
- B. 20/√2
- C. 20/π
- D. 20π
Explanation: According to the formula;DC = 2V/πHere, V = 10V. So,DC = 2 (10) / πDC = 20/πHence, option C is the correct option.
Correct answer: 20/π- A. Vm
- B. Vm/√2
- C. 2Vm
- D. Vm/3
Explanation: For the explanation, presented below;FB stands for 'Forward Biased',KVL stands for Kirchhoff's Voltage Law, which is Kirchhoff's second…
Correct answer: 2Vm- A. Only one
- B. Two
- C. Three
- D. Four
Explanation: The carrier signal is a sine wave at the carrier frequency. The sine wave has three characteristics that can be altered.
Correct answer: Three- A. A full wave rectifier
- B. An amplifier
- C. A transmitter
- D. A half wave rectifier
Explanation: A semi-conductor diode, also known as crystal diode, can be used as a half-wave rectifier.STB Pg- 203
Correct answer: A half wave rectifier- A. Diode
- B. Transistor
- C. Transformer
- D. Inductor
Explanation: A diode is a semiconductor device that allows current to flow in one direction while blocking it in the opposite direction.
Correct answer: Diode- A. Is reverse biased
- B. Is forward biased
- C. Behaves as open
- D. Shows maximum resistance
Explanation: The correct statement is B. Is forward biased. During the positive half cycle of an AC input in a rectifier circuit, the diode should be…
Correct answer: Is forward biased- A. 1
- B. 2
- C. 3
- D. 4
Explanation: Half-wave rectification allows only one half of the AC signal to pass through, which is achieved using a single diode.
Correct answer: 1- A. Ie = Ic + Ib
- B. Ie = Ic - Ib
- C. Ie = Ib / Ic
- D. Ie = Ic * Ib
Explanation: This is the correct relationship between the emitter current (Ie), collector current (Ic), and base current (Ib) in an NPN transistor.
Correct answer: Ie = Ic + Ib