Description : Why are drum-type armatures preferred over the Gramme ring armature in modern dc generators?
Last Answer : Drum-type armatures are more efficient, because flux lines are cut by both sides of each coil.
Description : Why is the Gramme-ring armature not more widely used
Last Answer : Only outside of coils cut flux (inefficient).
Description : What type of rotor is used in split-phase motors? A. Drum B. Salient pole C. Squirrel-cage D. Wound-rotor
Last Answer : Answer: C
Description : Which of the following describes the action when the handle is moved to the start position of a drum-type motor controller used with a compound motor? A. Full current is supplied to the shunt field, ... armature. D. Reduced line current is supplied to the shunt field, series field, and armature.
Description : A series wound DC motor has its armature and field connected in series with a resistor. When the motor is disconnected from its power supply, this motor will exemplify __________. A. the ... the proper connections for an automatic strip heater C. a reversing controller circuit D. dynamic braking
Last Answer : Answer: D
Description : In a series wound motor, the current passing through the field windings is also passing through the _____________. A. armature B. shunt field C. reactance comparator D. laminations
Last Answer : Answer: A
Description : A shunt-wound DC generator is one in which the shunt field windings are in parallel with the _____________. A. commutator B. brushes C. armature D. all of the above
Description : A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is (A) 96 V (B) 192 V (C) 384 V (D) 768 V
Last Answer : A 8-pole, DC generator has a simplex wave-wound armature containing 32 coils of 6 turns each. Its flux per pole is 0.06 Wb. The machine is running at 250 rpm. The induced armature voltage is 384 V
Description : The induced emf in the armature of a lap -wound four -pole dc machine having 100 armature conductors rotating at 600 rpm and with 1 Wb flux per pole is (1) 1000V (2) 100V (3) 600V (4) 10,000V
Last Answer : The induced emf in the armature of a lap -wound four -pole dc machine having 100 armature conductors rotating at 600 rpm and with 1 Wb flux per pole is 1000V
Description : Tracks on each channel of a magnetic drum are grouped into what?
Last Answer : Sectors.
Description : How does a magnetic drum differ from a magnetic disk?
Last Answer : The tracks in which the data is stored are assigned to channels that form circular bands around the drum.
Description : Please ripley me due to emergency
Last Answer : To calculate the flux density in the ring, you need to use the following formula: B = (μ * I * N) / (2 * π * r) where: B is the flux density in the ring (in teslas) μ is the relative permeability ... 2 * π * 0.127 m) = 0.53 T So the flux density in the ring would be approximately 0.53 teslas.
Description : A conducting light string is wound on the rim of a metal ring of radius `r` and mass `m`. The free end of the string is fixed to the ceiling. A vertic
Last Answer : A conducting light string is wound on the rim of a metal ring of radius `r` and mass `m`. ... function of time. b. the terminal velocity of the ring.
Description : An iron ring of mean circumference 80 cm is uniformly wound with 500 turns of wire and carries 0.8A. Find the magnetic field strength.
Last Answer : Ans: Magnetic field strength H = NI /l = 500 x 0.8 / 80 x 10-2 = 500 AT/m
Description : Which one is not present in AC generator: a. Armature b. magnet c. slip ring d. commutator
Last Answer : c. slip ring
Description : What is the disadvantage of using a double receiver instead of two individual receivers?
Last Answer : If one of the receivers goes bad the entire unit must be replaced.
Description : What is the main disadvantage of parallel transfer?
Last Answer : Requires more circuitry.
Description : What is the main disadvantage of a conventional full-wave rectifier?
Last Answer : Peak voltage is half that of the half-wave rectifier.
Description : Name a disadvantage of sine-wave oscillator synchronizers.
Last Answer : It requires additional shaping circuits.
Last Answer : . It requires additional shaping circuits.
Description : What is the main disadvantage of the conventional full wave rectifier?
Last Answer : The peak voltage is half that of a half-wave rectifier.
Description : What is the major disadvantage of printed circuit boards?
Last Answer : Components soldered in place.
Description : What is the major disadvantage of an fm signal as compared to an AM signal?
Last Answer : Wide bandpass.
Description : What is a disadvantage of agc?
Last Answer : Weak signals produce bias, which could result in no usable receiver output.
Description : What is the main disadvantage of PROM?
Last Answer : If a mistake is made and entered, it cannot be corrected or erased.
Description : What is the main disadvantage of a series motor?
Last Answer : It must have a load connected to avoid damage from excess speed.
Description : What is the main disadvantage of series generators?
Last Answer : Output voltage varies as the load varies
Description : What is a disadvantage of a direct-current system with respect to supply voltage?
Last Answer : the dc voltage must be generated at the level required by the load.
Description : What is the main disadvantage of using fiber-optic cables?
Last Answer : High attenuation.
Description : What is the primary disadvantage of the pointer arrangement for indicating coil rotation?
Last Answer : Coil balance.
Description : What is the main disadvantage of the rhombic antenna?
Last Answer : It requires a large antenna site.
Description : What is the main disadvantage of pulse-position modulation?
Last Answer : It requires synchronization between the transmitter and receiver.
Description : What is a major disadvantage of a carbon microphone?
Last Answer : Background hiss resulting from random changes in the resistance between individual carbon granules.
Last Answer : Antenna-to-ground capacitance can cause the oscillator frequency to vary.
Description : If two coils are wound on a single iron core, what will a change in current in one coil cause in the other coil?
Last Answer : A change in inductance.
Description : Armature reaction in a dc motor causes a shift of the neutral plane in which direction?
Last Answer : Opposite the rotation.
Description : What is armature reaction?
Last Answer : Distortion of the main field due to the effects of armature current.
Description : In single-phase alternators, in order for the voltages induced in all the armature windings to add together for a single output, how must the windings be connected?
Last Answer : In series.
Description : How is the applications software compatibility problem overcome
Last Answer : Some software comes in several versions so it can run under several different operating systems.
Description : What type resistor should be used to overcome the disadvantages of the carbon resistor?
Last Answer : The wirewound resistor.
Description : How do closed-loop capstan drive tape transports overcome the disadvantages of the open-loop drive design?
Last Answer : Closed loop capstan drive transports use more than one capstan to clamp the tape in the area around the magnetic head.
Description : Which digital data encoding method helps overcome a tape recorder’s low-frequency response problems by recording two logic levels for each incoming data bit?
Last Answer : Bi-phase level encoding.
Description : What type of junctions are formed where the arms of a hybrid ring meet the main ring?
Last Answer : Basic E-type junctions.
Description : To propagate energy down an arm of a hybrid ring duplexer, the two fields at the junction of the arm and the ring must have what phase relationship?
Last Answer : 180 degrees out of phase
Description : Capacitive tuning by inserting a ring into the cavity slot of a magnetron is accomplished by what type of tuning mechanism?
Last Answer : . A cookie-cutter tuner
Description : Which topology (bus, ring, star, or tree) has a center hub interconnecting the equipments?
Last Answer : Star.
Description : What is the purpose of the guard ring in a megohmmeter?
Last Answer : Shunts leakage current, which prevents false readings
Description : Can Arduino be used for building an electronic drum kit?
Last Answer : Yes, Arduino can be used for building an electronic drum kit by using piezo sensors to detect the drum hits, and by using MIDI communication to produce the corresponding sounds.