Description : Process of conversion low voltage to high voltage is called _______ (a) Rectification (b)forward bias (c) reverse bias (d) amplification
Last Answer : (d) amplification
Description : For which one of the following, 'Diodes' are generally used for? (1) Rectification (2) Amplification (3) Modulation (4) Filtration
Last Answer : (1) Rectification Explanation: In electronics, a diode is an electronic device that allows current to flow in one direction only. It is mainly used as a rectifier diode that lets ... used for power supply operation. Rectifier diodes are used for changing alternating current into direct current.
Description : For which one of the following, "Diodes' are generally used for? (1) Rectification (2) Amplification (3) Modulation (4) Filtration
Last Answer : (1) Rectification Explanation: A rectifier diode is a two-lead semiconductor that allows current to pass in only one direction. Many types of diodes are used for a wide range of applications. Rectifier diodes are a vital component in power supplies
Description : For which one of the following, ‘Diodes’ are generally used for? (1) Rectification (2) Amplification (3) Modulation (4) Filtration
Last Answer : Rectification
Description : Which of the following converts electric energy into mechanical energy: a. Transformer b. DC generator c. Motor d. AC generator
Last Answer : d. AC generato
Description : Laser is the acronym for a) Light Amplification by Stimulated Emission of Radiation b) Light Amplification by Spontaneous Emission of Radiation c) Light Amplified by Stimulated Emission of Radiation d) Light Amplification by Standard Emission of Radiation
Last Answer : a) Light Amplification by Stimulated Emission of Radiation
Description : Explain what happens if a DC motor is fed with AC supply
Last Answer : Motor will run at low speed, sparking at brushes, heat due to eddy current will finally burn the motor.
Description : What do we use for welding on ships? AC or DC?
Last Answer : Ask E/O on your ship.
Description : The output from a full wave rectifier is (a) A pulsating uni-directional current (b) A DC voltage (c) Zero (d) An AC voltage
Last Answer : a) A pulsating uni-directional current
Description : In a half wave rectifier the rms value of AC component of the waves (a) Zero (b) Equal to DC value (c) More than DC value (d) Less than DC value
Last Answer : b) Equal to DC value
Description : The only difference between construction of DC generator and Ac generator is that of: a. carbon brush b. Bar magnet c. electromagnet d. Horseshoe magnet
Last Answer : b. Bar magnet
Description : For which Diode is used ? (1) modulation (2) oscillation (3) amplification (4) purification
Last Answer : purification
Description : An ac voltmeter using full -wave rectification and having a sinusoidal input has an ac sensitivity equal to (1) 1.414 times dc sensitivity (2) dc sensitivity (3) 0.9 times dc sensitivity (4) 0.707 times dc sensitivity
Last Answer : An ac voltmeter using full -wave rectification and having a sinusoidal input has an ac sensitivity equal to 0.9 times dc sensitivity
Description : What are the importances of conversion of AC into DC?
Last Answer : a. For traction purpose a DC series motor is most important. Examples in railways, in electrical lifts etc. b. For electrolytic and electro chemical processes such as electro plating, electrolysis, ... arc welding. d. It is required for operating relays, timer, telephone, circuit breakers etc.
Description : Which of the following steps is/are not required for analog to digital conversion ? (a) Sensing (b) Conversion (c) Amplification (d) Conditioning (e) Quantization Codes : (A) (a) and (b) (B) (c) and (d) (C) (a), (b) and (e) (D) None of the above
Last Answer : (D) None of the above
Description : What is the conversion between. AC to AC ? DC to DC? AC to DC? DC to AC ?
Last Answer : 1.ac to ac is regulation 2.dc to dc is chopper 3.ac to dc is rectifier 4.dc to ac is inverter
Description : Which method is not used for conversion of AC to DC? A. Motor-generator set B. Rotary converter C. Metal rectifiers D. Dynamometers
Last Answer : Dynamometers method is not used for conversion of AC to DC.
Description : What are the basic parts of a DC motor?*
Last Answer : Rotor and stator, field poles, commutator, brushes, fan impeller, bearing & housing, end covers and name plate.
Description : How is the speed of a DC motor varied?
Last Answer : To vary the speed of a DC motor we need a constant voltage power supply with a series POT resistor of higher watt rating. A Pulse Width Modulator (PWM) can be used.
Description : Why is DC not much in use now?
Last Answer : AC generators are a better technology and voltage transformation (by transformers) is easy is possible in AC and not DC.
Description : Is there phase in DC?
Last Answer : No
Description : Which component is mainly used in a DC generator: a.slip ring b. commutator c. magnet d. coil
Last Answer : b. commutator
Description : Direct Current (DC) Next Topic : Alternating current (AC)
Last Answer : Direct Current (DC) is the unidirectional electric current. Uni meaning is one. And the flow of charge in same direction. We know that conventional current flow from positive terminal of battery to ... The magnitude of DC may constant or vary but direction do not change with respect to time.
Last Answer : Primary Idea : - First Home Type Understand AC To buy Will be That In the room AC Put it on In that If The window Stays However Likes According to Good Brand See ' window AC ' Bought To take Can. Of ... go 45 From 60 Thousands Money In The same Price In ' Gree ' Of the brand Window AC Found Will go
Description : Where is a rotor wound AC motor used?
Last Answer : For starting heavy torques, mostly used on portable machines and small winches.
Description : How can the direction of rotation of an AC motor be reversed?*
Last Answer : By interchanging any two supply lines.
Description : What are the parts of a brushless AC generator?
Last Answer : Yoke, armature, stator, rotor, primary exciter, main exciter, rotary diode rectifier assembly, impeller, bearing & housing, end cover, terminal block, AVR.
Description : What is meant by phase in AC?
Last Answer : Two or more AC voltages or currents that are out of step with each other. Their peaks and zero points do not match up at the same points in time. This is meant by phase.
Description : Capacity of battery fuse in AC Coaches a. 315 A & 400 (HRC ) c. 16 A (HRC ) b. 63 A (HRC ) d. 5 A (HRC )
Last Answer : a. 315 A & 400 (HRC )
Description : In the plane of AC generator coil is parallel to the field, then emf induced in coil is: a. maximum b. minimum c. zero d. intermediate
Last Answer : b. minimum
Description : Which one is not present in AC generator: a. Armature b. magnet c. slip ring d. commutator
Last Answer : c. slip ring
Description : The most common source of AC voltage is: a. motor b. generator c. cell d. transformer
Last Answer : c. cell
Description : The principle of AC generator is: a. Mutual induction b. self induction c. electromagnetic induction d. Induction
Last Answer : b. self induction
Description : Turn ratio of a transformer is 5. If 220 V AC is applied to its primary coil, voltage in the secondary coil will be: a. 44V b. 4.4 V c. 220V d. 1100V
Last Answer : c. 220V
Description : Alternating current (AC)
Last Answer : AC stands for Alternating Current meaning voltage or current that changes polarity or direction respectively over time. An Alternating Current (AC) is an electric current whose magnitude ... energy are known as alternators and are simpler construction than DC electromechanical generators.
Description : The process of dividing an analog signal into a string of discrete outputs, each of constant amplitude, is called: (A) Strobing (B) Amplification (C) Conditioning (D) Quantization
Last Answer : (D) Quantization
Description : What is rectification ?
Last Answer : : The method by which AC voltage is converted to DC voltage is called rectification.
Description : If the purchase hook is undermasted, the purchase account is debited in rectification.
Last Answer : State whether the following statement are True or False with reason : If the purchase hook ... , the purchase account is debited in rectification.
Description : For a binary mixture with low relative volatility, continuous rectification to get pure products will require (A) Low reflux ratio (B) Less number of trays (C) Small cross-section column (D) High reflux ratio
Last Answer : (D) High reflux ratio
Description : Deaeration (removal of O2 ) of water is done by (A) Rectification (B) Absorption (C) Ion-exchange (D) Adsorption
Last Answer : (C) Ion-exchange
Description : Mark incorrect option relating to when In correct items noticed in a sub office daily account a) Should be communic b) A similar note should be made in the sub office daily account received ... The daily account received from a SO should be returned for rectification of errors d) None of these
Last Answer : c) The daily account received from a SO should be returned for rectification of errors
Description : Define rectification efficiency. Give its formula.
Last Answer : The ratio of output DC power delivered to the load to the applied input AC power is called rectification efficiency. It is denoted by η. η = Output DC power delivered to the load / Input AC power from transformer secondary η = Pdc / Pac
Description : The r.m.s. value of a half-wave rectified alternating current is 10 A. Its value for full-wave rectification will be
Last Answer : The RMS value of a half-wave rectified current is 10 Ampere. Its value for full-wave rectification would be: 14.14 Ampere
Description : Rectification efficiency of a full wave rectifier without filter is nearly equals to: (1) 51% (2) 61% (3) 71% (4) 81%
Last Answer : Rectification efficiency of a fullwave rectifier without filter is nearly equals to: 81%
Description : Laser beams can generate three dimensional images of objects in a process called a) polygraphy b) telegraphy c) holography d) autography
Last Answer : c) holography
Description : The reverse process of photo-electric effect is called: a) Annihilation of matter b) Compton effect c) Pair production d) X-rays
Last Answer : d) X-rays
Description : The photo copying process is called: (a) Xerography (b) Inkjet printer (c) Both (a) and (b) (d) None of these
Last Answer : (a) Xerography
Last Answer : Operating Of the system Of work Basic Single Who Process Says.
Description : The termdispersion describestheprocessof a.separatinglightinto its componentfrequencies b. reflecting light from a smooth surface c. the process by which light is absorbed by an uneven rough surface d. light scattering
Last Answer : a.separatinglightinto its componentfrequencies
Description : Depletion region of a junction is formed _________ (a) during the manufacturing process (b) under forward bias (c) under reverse bias (d) when temperature varies
Last Answer : (a) during the manufacturing process