intro
Question 1:
What will be the resultant output ripple frequency in a bridge full wave rectifier, where the input sine wave frequency is 50Hz?
Topic: Frequency in Full Wave Rectifier
Correct Answer: B) 100Hz
- In the context of a full-wave rectifier, the ripple frequency is given by the formula 2 × Frequency of the source.
- By replacing the frequency of the source (50Hz) into the formula, the ripple frequency can be calculated as 2 × 50Hz = 100Hz.
- Therefore, the correct answer is B) 100Hz.
Question 2:
In the process of rectification, which circuit is utilized to achieve a steady output voltage?
Topic: Circuits in Rectification
Correct Answer: C) Filters
- In the full-wave rectification process, the resultant output voltage is typically pulsating.
- To achieve a more stable or smooth output voltage, a specific type of circuit known as a 'filter' is commonly used.
- Therefore, the correct answer is C) Filters.
Question 3:
Choose the correct schematic representation of a half-wave rectifier.
Topic: Half-wave Rectifier
Correct Answer: B) Option 2
- A half-wave rectifier is a circuit designed with a diode to convert AC voltage into DC voltage.
- In this circuit, only one half of the input sine wave (either positive or negative) is passed, while the other half is blocked.
- In this context, the correct schematic representation is given by Option 2.
Question 4:
During half-wave rectification, when is the output DC voltage obtained across the load?
Topic: Half-wave Rectification
Correct Answer: C) Only during the alternate half cycles of the input AC
- Half-wave rectification is characterized by the flow of output only during alternate half cycles of the input AC.
- Even though the input AC has full cycles, the DC output is only obtained during one half of these cycles.
- Therefore, the correct answer is C) Only during the alternate half cycles of the input AC.
Question 5:
What is the process called where Alternating Current (AC) is transformed into Direct Current (DC)?
Topic: AC to DC Conversion
Correct Answer: C) Rectification
- The process that converts an Alternating Current (AC) into a Direct Current (DC) is known as "Rectification".
- This process is fundamental in power supplies and involves the conversion of high-frequency AC into continuous DC.
- Therefore, the correct answer is C) Rectification.
Question 6:
When a half-wave rectifier and a full-wave rectifier are used with an AC voltage of 100V peak value, what would be the respective rms values of outputs?
Topic: RMS Output Voltage in Rectifiers
Correct Answer: C) 50V and 70V
- In a half-wave rectifier, the rms output voltage (Vrms) is calculated as the peak input voltage divided by 2 (Vrms = Vo/2). This gives us 50V for a 100V peak input.
- In a full-wave rectifier, the rms output voltage is calculated as around 70% of the peak input voltage (Vrms = 0.7Vo). This gives us 70V for a 100V peak input.
- Therefore, the correct answer is C) 50V and 70V.
Question 7:
Given an input across terminals "A" and "C", and output across "B" and "D", what would the output look like in the provided figure?
Topic: Output in Full Wave Rectifier
Correct Answer: C) Full wave rectified
- The diagram provided depicts a full wave rectifier configuration, taking input from terminals "A" and "C" and relaying the output across "B" and "D".
- In this setup, the output is a full wave rectified version of the input.
- The correct answer, therefore, is C) Full wave rectified.
Question 8:
In an N-P-N transistor, which part is represented by the 'p'?
Topic: N-P-N Transistor
Correct Answer: C) Base
- An N-P-N transistor consists of three parts: the collector, base, and emitter.
- In this specific type of transistor, the 'p' section refers to the 'base'.
- Therefore, the correct answer is C) Base.
Question 9:
For half-wave rectification, where should a capacitor be correctly placed to act as a smoothing device as shown in the following diagrams?
Topic: Capacitor Placement in Half-Wave Rectifier
Correct Answer: D) Diagram D
- To achieve a smoother voltage output in a half-wave rectifier, a filtering device such as a capacitor is used.
- This capacitor should be connected in parallel with the load for effective smoothing.
- Thus, the correct placement is depicted in Diagram D. So, the correct answer is D) Diagram D.
Question 16:
If a half-wave rectifier is used to rectify an AC voltage with a frequency of 50 Hz, how many pulses of rectified current would be obtained in one second?
Topic: Pulse Frequency in Half-Wave Rectification
Correct Answer: A) 50
- A half-wave rectifier only allows one half of an AC cycle (either positive or negative) to pass through.
- This means that the pulse frequency or ripple frequency in half-wave rectification is equal to the frequency of the source.
- Therefore, the correct answer is A) 50.
Question 17:
What would be the ripple frequency of the output voltage when a full wave rectifier is fed with an AC voltage of 60 Hz?
Topic: Ripple Frequency in Full-Wave Rectification
Correct Answer: C) 120 Hz
- In a full-wave rectification process, both positive and negative halves of the AC cycle are converted into pulsating DC.
- Thus, the ripple frequency or pulse frequency in full-wave rectification is twice the frequency of the source.
- As a result, the correct answer is C) 120 Hz.
Question 18:
In the illustrated circuit, what is the expected current traversing the resistor?
Topic: Current Flow in a Reverse-Biased Circuit
Correct Answer: D) None of these
- In the given circuit diagram, the diode is reverse-biased.
- In a reverse-biased state, a diode does not permit current flow, essentially functioning as an open switch.
- Therefore, practically no current would flow through the resistor, making the correct answer D) None of these.
Question 19:
Identify the diode that is in a forward-biased state in the given circuit.
Topic: Identifying Forward-Biased Diodes
Correct Answer: D) Diode D
- A diode is said to be in a forward-biased state when the higher potential (positive terminal) is connected to the p-type material and the lower potential (negative terminal) is connected to the n-type material.
- In the provided circuit, Diode D is connected such that -5V (which is of higher potential compared to -12V) is connected to the p-side, making it forward-biased.
- Consequently, the correct answer is D) Diode D.
Question 20:
How many diodes are involved in the bridge rectifier's full wave rectification process?
Topic: Diode Count in Full-Wave Bridge Rectification
Correct Answer: B) Four
- Bridge rectification is a method used in rectifiers to convert alternating current (AC) input into direct current (DC) output.
- The term 'bridge' in bridge rectifier refers to the configuration of diodes that forms a bridge circuit across the input source.
- For full-wave rectification in a bridge rectifier, four diodes are used in a specific formation to ensure that both halves of the AC cycle are converted into DC output.
- Therefore, the correct answer to the question is B) Four.