1 Answer

Answer :

As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for sound equipment.

Related questions

Description : What is magnetic hysteresis? What is the cause of hysteresis?

Last Answer : Magnetic hysteresis: When a magnetic material is subjected to cycle of magnetization, it is found that flux density (B) in the material lags behind applied magnetizing force (H). This ... the movement of orientation, due to which the flux density lags behind the magnetic field intensity.

Description : In a magnetic material hysteresis loss takes place primarily due to?

Last Answer : In a magnetic material hysteresis loss takes place primarily due to it high retentivity.

Description : Explain hysteresis loss, eddy current loss and skin effect limitations with reference to magnetic material.

Last Answer : Hysteresis loss: Hysteresis loss is a loss which occurs due to the friction of magnetic domain due to the change in magnetic field in ferromagnetic material like iron. Hysteresis loss causes power loss ... loss in transformer is given by, We=Kef2Kf2Bm2watts Skin effect limitations:

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Last Answer : In a hysteresis motor, the rotor must have retentivity.

Description : Explain the hysteresis loop of a magnetic material with neat diagram.

Last Answer : Hysteresis loop of magnetic material:  The circuit arrangement for plotting the hysteresis loop is shown in figure given below. The electromagnetic part consists of a coil wound on the iron ring ... one magnetic reversal is called hysteresis loop. Meaning of hysteresis is to lag behind.

Last Answer : The mechanical power developed by a shunt motor will be maximum when the ratio of back e.m.f. to applied voltage is 0.5.

Description : Damper winding is provided in 3 phase synchronous motors to :

Last Answer : Damper winding is provided in 3 phase synchronous motors to : provide starting torque and prevent hunting

Description : Stepper motors are used in  (1) printers (2) lifts (3) amplifiers (4) oscillators

Last Answer : Stepper motors are used in printers 

Description : Slot harmonics are reduced in induction motors by using (A) fractional-pitch windings (B) fractional-slot windings (C) integral-slot windings (D) distributed windings

Last Answer : Slot harmonics are reduced in induction motors by using fractional-slot windings

Description : Generally, Crawling in squirrel cage induction motors is tendency to run stably at speeds as low as (A) One-third of their synchronous speed (B) One-fifth of their synchronous speed (C) One-seventh of their synchronous speed (D) One-ninth of their synchronous speed

Last Answer : Generally, Crawling in squirrel cage induction motors is tendency to run stably at speeds as low as One-seventh of their synchronous speed

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Last Answer : Which of the following test is usually conducted to determine the efficiency of traction motors ? (A) Field’s test (B) Swinburne’s test (C) Hopkinson’s test (D) Retardation test.

Description : Which of the following motors is being extensively used in servo applications ? A. AC motor B. Field controlled dc motor C. Armature controlled dc motor D. None of these

Last Answer : Which of the following motors is being extensively used in servo applications ? A. AC motor B. Field controlled dc motor C. Armature controlled dc motor D. None of these

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Last Answer : In case of conductively compensated D.C. series motors, the compensating winding is provided in series with armature winding.

Last Answer : In case of D.C. shunt motors the speed is dependent on back e.m.f. only because flux is practically constant in D:C. shunt motors.

Last Answer : A direct online starter is used for starting motors up to 5 H.P.

Last Answer : When two D.C. series motors are connected in parallel, the resultant speed is normal speed.

Last Answer : In D.C. shunt motors as load is reduced the speed will remain almost constant.

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Last Answer : Differentially compound D.C. motors can find applications requiring low starting torque.

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Last Answer : Most of the fractional horsepower motors have either plain or sleeve bearings.

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Description : Describe with neat sketch working of hysteresis motor.

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Last Answer : i) Flux density ii) Frequency iii) Volume of the magnetic material iv) Nature of magnetic material

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Last Answer : The term hysteresis is associated with On-Off control

Description : If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be?

Last Answer : If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be large.

Last Answer : A hysteresis motor works on the principle of hysteresis loss.

Last Answer : The direction of rotation of an hysteresis motor is determined by position of shaded pole with respect to main pole.

Description : What is the difference between eddy current and hysteresis loss?

Last Answer : Loss occurred by magnetising and demagnetising process is called histerisis loss and the current flowed due to the magnetic field produced by the electric field applied is called eddy current losses

Description : What are the factors to be considered while selection of motors for different drives?

Last Answer : Following Factors are considered while selecting electric drive (Motor) for particular application:  Factors to be considered for selection of Electrical Drives:  1) Nature of Supply:- Whether supply ... , load equalization 7) Cost: - Capital, Running and maintenance cost should be less.  

Description : Briefly explain how an electrical generator converts mechanical energy into electrical energy.

Last Answer : Working principle of DC generator: * Working principle of DC generator is the principle of dynamically induced emf or electromagnetic induction. * According to this principle, when flux is cut by a conductor, an ... , the flux is cut by the armature winding and an emf is dynamically induced in it. 

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Description : Explain the mechanical properties of insulating materials.

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Description : In a d.c. motor, the mechanical output power actually comes from?

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Description : SINGLE PHASE INDUCTION MOTORS MCQ

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Description : THREE PHASE INDUCTION MOTORS MCQ

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