Answer :
Direction of rotation of a split phase motor can be reversed by reversing the connection of either running winding or starting winding.
asked
Mar 20, 2018
by
anonymous
Answer :
In case of a shaded pole motor the direction of rotation of the motor is from main pole to shaded pole.
asked
Mar 20, 2018
by
anonymous
Answer :
In repulsion motor direction of rotation of motor is the same as that of brush shift.
asked
Mar 20, 2018
by
anonymous
Description : The direction of rotation of an inverter fed 3-phase ac motor is reversed by (A) a mechanical reversing switch (B) reversing the input dc link voltage (C) operating the inverter as a rectifier (D) changing the sequence of switching
Answer :
The direction of rotation of an inverter fed 3-phase ac motor is reversed by changing the sequence of switching
asked
Apr 28, 2018
by
anonymous
Answer :
The direction of rotation of a D.C. series motor can be changed by interchanging field terminals.
asked
Mar 20, 2018
by
anonymous
Answer :
The direction of rotation of universal motor can be reversed the by reversing the flow of current through either armature winding or field winding.
asked
Mar 20, 2018
by
anonymous
Description : How can we reverse the direction of rotation of synchronous motor?
Answer :
By reversing supply phase sequence we can reverse the direction of rotation of synchronous motor.
asked
Mar 18, 2018
by
anonymous
Description : In a synchronous machine, if the field flux axis ahead of the armature field axis in the direction of rotation, the machine is operating as (1) synchronous motor (2) synchronous generator (3) asynchronous motor (4) asynchronous generator
Answer :
In a synchronous machine, if the field flux axis ahead of the armature field axis in the direction of rotation, the machine is operating as synchronous generator
asked
May 1, 2018
by
anonymous
Answer :
To reverse the direction of rotation of a capacitor start motor while it is running we should disconnect motor from the supply till it stops then reconnect it to supply with reversed connection of main or auxiliary winding.
asked
Mar 20, 2018
by
anonymous
Description : how can we reverse the direction of rotation of three phase induction motor ?
Answer :
The direction of rotation of three phase induction motor can be reversed by plugging i.e by changing any two out of three phases of the supply to the stator of the Induction motor terminal.
asked
Oct 4, 2017
by
anonymous
Answer :
A hysteresis motor works on the principle of hysteresis loss.
asked
Mar 20, 2018
by
anonymous
Description : In a single-phase induction motor, the operating direction is determined by the ________ A) Rotor B) Stator C) Starting circuit D) None of these
Answer :
In a single-phase induction motor, the operating direction is determined by the Starting circuit
asked
Apr 29, 2018
by
anonymous
Description : Describe with neat sketch working of hysteresis motor.
Answer :
Working: When stator is energized with single phase ac supply, rotating magnetic field is produced because of starting (auxiliary) and main windings, which remain in circuit permanently. The ... the principle of magnetic locking this motor either rotates at synchronous speed or not at all.
asked
May 7, 2020
by
anonymous
Answer :
The rotor of a hysteresis motor is made of chrome steel.
asked
Mar 20, 2018
by
anonymous
Answer :
In a hysteresis motor, the rotor must have retentivity.
asked
Mar 20, 2018
by
anonymous
Description : The direction of rotation of hysteresis motor is determined by the: (A) Resistivity of the rotor material. (B) Amount of hysteresis loss. (C) Permeability of rotor material. (D) Position of shaded pole w.r.t main pole.
asked
Apr 5, 2018
by
anonymous
Description : The efficiency of two identical transformers under load conditions can be determined by?
Answer :
The efficiency of two identical transformers under load conditions can be determined by back-to-back test.
asked
Mar 19, 2018
by
anonymous
Description : What is magnetic hysteresis? What is the cause of hysteresis?
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.
asked
Sep 4, 2018
by
anonymous
Description : State the factors affecting hysteresis loss.
Answer :
i) Flux density ii) Frequency iii) Volume of the magnetic material iv) Nature of magnetic material
asked
Sep 4, 2018
by
anonymous
Description : Explain the hysteresis loop of a magnetic material with neat diagram.
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.
asked
Aug 8, 2018
by
anonymous
Description : Hysteresis is commonly found in ______ A) ferromagnetic materials B) ferroelectric materials C) both A and B D) none of these
Answer :
Hysteresis is commonly found in ______ A) ferromagnetic materials B) ferroelectric materials C) both A and B D) none of these
asked
Apr 29, 2018
by
anonymous
Description : The term hysteresis is associated with (A) On-Off control (B) P-I control (C) Feed forward control (D) Ratio control
Answer :
The term hysteresis is associated with On-Off control
asked
Apr 26, 2018
by
anonymous
Description : If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be?
Answer :
If the area of hysteresis loop of a material is large, the hysteresis loss in this material will be large.
asked
Mar 25, 2018
by
anonymous
Description : In a magnetic material hysteresis loss takes place primarily due to?
Answer :
In a magnetic material hysteresis loss takes place primarily due to it high retentivity.
asked
Mar 25, 2018
by
anonymous
Answer :
As hysteresis motors are free from mechanical and magnetic vibrations therefore these are considered as suitable for sound equipment.
asked
Mar 20, 2018
by
anonymous
Description : What is the difference between eddy current and hysteresis loss?
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
asked
Mar 15, 2018
by
anonymous
Description : Explain hysteresis loss, eddy current loss and skin effect limitations with reference to magnetic material.
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:
asked
Feb 16, 2018
by
anonymous
Description : What happens when you reverse the direction of the current in an electromagnet?
Answer :
When you reverse current direction in an electromagnet, the magnetic poles will also change.
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of an AC current?
Answer :
The magnitude and direction of alternating current is changes with respect to time. So for half cycle it is positive and for next half cycle it is negative.
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of flow of electric current in an electric circuit?
Answer :
It flows from anode to cathode (direction of holes flow)
asked
Mar 14, 2018
by
anonymous
Description : The direction of rotation of a 3-phase induction motor is clockwise when it is supplied with 3-phase sinusoidal voltage having phase sequence A-B-C. For counter clockwise rotation of the motor, the phase sequence of the power supply should be (A) B-C-A (B) C-A-B (C) A-C-B (D) B-C-A or C-A-B
Answer :
The direction of rotation of a 3-phase induction motor is clockwise when it is supplied with 3-phase sinusoidal voltage having phase sequence A-B-C. For counter clockwise rotation of the motor, the phase sequence of the power supply should be A-C-B
asked
May 17, 2018
by
anonymous
Description : Two non-collinear parallel equal forces acting in opposite direction?
Answer :
Two non-collinear parallel equal forces acting in opposite direction constitute a couple.
asked
Mar 22, 2018
by
anonymous
Description : What is the direction of flow when charging a capacitor?
asked
Mar 15, 2018
by
anonymous
Description : How does AC current change direction?
Answer :
This is because the angle at which the magnetic fields cuts across a winding changes its poles thus current has to change dirention .
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of the induced electric field?
Answer :
It is in opposite direction to the one that produced it.
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of the induced current?
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of the electric field?
Answer :
Electric field is at right angle widh flow of current (right hand rule).
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of flow of current?
Answer :
Current flows from anode to cathode(opposite direction to flow of electrons)
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of the flow of electrons?
Answer :
Electrons flow cathode to anode or in an oposite direction of convection current flow or holes.
asked
Mar 14, 2018
by
anonymous
Description : What is the direction of the conventional current flow?
Answer :
The conventional current flow in opposite direction of flow of electrons. The electrons flow from negative terminal of battery to positive terminal of battery. And conventional current flow from positive terminal of battery to negative terminal of battery.
asked
Mar 14, 2018
by
anonymous
Description : why current flows in opposite direction of electrons?
Answer :
Hi team, the current flow is nothing but flow of electrons But the conventional direction I'd opposite to actual current flow . ..
asked
Oct 3, 2017
by
anonymous
Answer :
Yes DIAC can conduct in both direction.
asked
Sep 20, 2017
by
anonymous
Answer :
The speed of a universal motor is generally reduced by using gear trains.
asked
Mar 20, 2018
by
anonymous
Answer :
In a capacitor start single-phase motor, when capacitor is replaced by a resistance motor will continue to run in same direction.
asked
Mar 20, 2018
by
anonymous
Description : A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will?
Answer :
A capacitor-start single phase induction motor is switched on to supply with its capacitor replaced by an inductor of equivalent reactance value. It will not start at all.
asked
Mar 20, 2018
by
anonymous
Answer :
In a shaded pole single-phase motor, the revolving field is produced by the use of shading coils.
asked
Mar 20, 2018
by
anonymous
Answer :
The rotor developed by a single-phase motor at starting is zero.
asked
Mar 20, 2018
by
anonymous
Answer :
Fleming's left hand rule.
asked
Sep 27, 2017
by
anonymous
Description : The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be?
Answer :
The number of poles in a phase induction motor at 50 Hz and running at 1500 rpm will be 4.
asked
Mar 26, 2018
by
anonymous
Answer :
When a D.C. series motor is connected to A.C. supply, the power factor will be low because of high inductance of field and armature circuits.
asked
Mar 20, 2018
by
anonymous