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 14 of 33
- A. 25 Hz
- B. 50 Hz
- C. 100 Hz
- D. Zero
Explanation: In full wave rectification ripple frequency is twice the input frequency.Whereas, for a half wave rectifier it is equal to the AC supply…
Correct answer: 100 Hz- A. 4
- B. 1
- C. 3
- D. 2
Explanation: One diode is needed in a half-wave rectifier. This diode limits the current flow in one direction.
Correct answer: 1- A. 25 Hz
- B. None of these
- C. 50 Hz
- D. 100 Hz
Explanation: The ripple frequency of a full-wave rectifier is twice its input frequency.
Correct answer: 100 Hz- 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. The positive half cycle of input AC
- B. The negative half cycle of input AC
- C. The positive and negative half cycles of input AC
- D. Either positive or negative half cycle of input
Explanation: The correct answer is "a) The positive half cycle of input AC." Half-wave rectification produces an output DC voltage only during the…
Correct answer: The positive half cycle of input AC- 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. None of these
Explanation: Transistors can be used as both half wave rectifiers and full wave rectifiers.Rectifiers are electronic devices used to convert…
Correct answer: Both- A. The positive half cycle of input AC
- B. The negative half cycle of input AC
- C. The positive and negative half cycles of input AC
- D. Either positive or negative half cycle of input AC
Explanation: In half wave rectification, the output DC voltage is obtained across the load for the positive half cycle of input AC, because during…
Correct answer: The positive half cycle of input AC- 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. Vm
- B. Vm/v2
- C. 2Vm
- D. Vm/3
Explanation: Using the concept of Peak Inverse Voltage, it can be found that if the input peak voltage is V, the Peak Inverse Voltage is 2 times.Hence…
Correct answer: 2Vm- A. Negative plate
- B. Positive plate
- C. Sight 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. Half wave
- 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. Any doubler
- B. Any tripler
- C. Any multiplication
- D. None of them
Explanation: The answer is any multiplier. A half-wave voltage multiplier can be cascaded with multiple stages to achieve any degree of voltage…
Correct answer: Any multiplication- A. One diode
- B. Two diodes
- C. Three diodes
- D. Four diodes
Explanation: RECTIFICATION:The conversion of AC into DC is called the rectification.RECTIFIER: A device used for rectification is called…
Correct answer: One diode- 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. 1.06 %
- B. 2.06 %
- C. 3.18 %
- D. 4.82 %
Explanation: wt= α =√(2Vr/Vp) =√2×2/100 = 0.2 radCycle at which the diode operates:= 0.2/2π × 100%= 0.2/6.28 ×100%= 3.18%Hence,C is the correct option.
Correct answer: 3.18 %- A. Modulation
- B. Amplification
- C. Oscillation
- D. Rectification
Explanation: A rectifier Converse alternating current to direct current and this process of converting AC to DC is known as rectification.
Correct answer: Rectification- A. 358.98 mW
- B. 275.2 mW
- C. 145.76 mW
- D. 456.78 mW
Explanation: The AC power input; PIN=IRMS2(RF+Rr).IRMS= Im/√2 = Vm/(Rf+RL)√2 = 30/[(1500+10) x 1.414] = 13.5mA.So, PIN= (13.5 x 10-3)2 x (1500+10)…
Correct answer: 275.2 mW- A. Half wave
- B. Full wave
- C. Bridge
- D. All of the above options are correct
Explanation: Option A: A half-wave rectifier converts an AC signal to DC by passing either the negative or positive half-cycle of the waveform and…
Correct answer: All of the above options are correct- A. 25
- B. 50
- C. 100
- D. 75
Explanation: The number of pulses per second in a rectified voltage will be equal to the input voltage .
Correct answer: 50