A transformer is a _____ device.

A. Static

B. Dynamic

C. Static and Dynamic

D. None of the above

Answer 

A. Static

Explanation 

• A transformer is a static electrical machine that transfers AC electric power from one circuit to another circuit at a constant frequency.
• A transformer is a static device that converts electrical power from one circuit to another without changing its frequency. So that input and out supply frequency always remain the same.
• Thus for a given 50 Hz input supply frequency, the output supply frequency is 50 Hz.
• A Transformer is used to convert low voltage (or high current) to high voltage (or low current) and high voltage to low voltage.
• It works on the principle of mutual induction.
• The primary coil has Np turns. The other coil, called the secondary coil, has Ns turns.
• Generally, the primary coil works as the input coil and the secondary coil works as the output coil of the transformer.
• When an AC voltage is applied to the primary coil, the resulting current produces an alternating magnetic flux that links the secondary coil and induces an emf in it. The value of this emf depends on the number of turns in the secondary.
• In a transformer, the load is connected to the secondary coil while the primary coil of a transformer is connected to an AC source.
• Mutual induction: By a change in the current in a circuit that is linked to another by the flux lines of a magnetic field, the production of an electromotive force in the circuit is called mutual induction.

Power System MCQs With Explanation 

 

• The advantages of high transmission voltage are
• The charging current drawn by the cable is
• The fact that current density is higher at the surface when compared to the center is known as
• In which of the following transmission lines capacitance effect is negligible?
• The distribution constant of the transmission line is
• Proximity effect is more in case of
• If the frequency is increased, then the skin effect will
• Bundled conductors in EHV transmission lines help in
• Which of the following produces radio interference in communication lines?
• Telecommunication lines are transposed to reduce the
• What is the function of economizer in Thermal Power Plant 
• Which of the following effects are associated with transmission line
• The insulator thickness on the conductor, in cables, depends upon
• By using a guard ring in a transmission line, its string efficiency
• If sag in an overhead line increase, the tension in the line
• Corona is accompanied by
• The conductor carries more current on the surface as compared to the core. This is called as
• Critical disruptive voltage is a voltage at which
• Bundled conductors are used for EHV transmission lines primarily for reducing the
• Low power factor is usually not due to
• Bonding is done at both ends of the cable to reduce the
• For Improving power factor
• Stock bridge dampers are used to
• Which of the following insulator is practically used for railway crossings?
• Which of the following decides the insulation level of 400 kV, EHV line?
• When earth fault occurs
• The minimum length of pipe electrode used for earthing should not be less than
• A ground wire is used to
• Earth resistance in typical domestic wiring is
• By which of the following systems electric power may be transmitted?
• Which of the following equipment will be most economical for regulating the voltage in the distribution feeder?

Transformer MCQs With Explanation 

• In a transformer the primary flux is 
• The noise of the transformer is mainly due to
• Buchholz relay is used for the protection
• Iron loss in a transformer can be determined by
• Oil is provided in an oil-filled transformer for
• In a star-delta transformer, the delta side phase voltage leads the star sides phase voltage by an angle
• Minimum voltage regulation occurs in transformer when the power factor of the load is
• The chemical used in the breather of a transformer should have the property of
• The power transformer can be termed as a constant
• In a transformer, which of the following losses are zero?
• Which of the following Transformer can have a tap changer?
• If the supply frequency (f) of a transformer decreases, the effect of frequency on the transformer's secondary output voltage?
• The primary winding of a transformer has a 120 V ac supply. What is the value of secondary voltage if the turn ratio is 10?
• The efficiency of a power transformer is _____ at full load.
• In a transformer the relation between the input frequency and the output voltage on secondary winding is _____.
• In a current transformer, _____ winding is closed.
• A transformer is a _____ device.
• A step-down transformer has _____ number of turns on primary winding and _____ number of turns on the secondary winding.
• A step-up transformer has _____ number of turns on primary winding and _____ number of turns on the secondary winding.
• Transformer works on ______ principle.
• Shell Type Transformer is mainly used for 
• A Magnetic Oil level Guage (MOG) is used in the Transformer to 
• The Function Of Power Transformer is/are
• The Radiators are used in transformers for 

Synchronous Motor MCQs With Explanation 

• In 3 -Φ synchronous motor if one of the phases is short-circuited the motor will
• The speed regulation of a synchronous motor is
• The negative phase sequence in a three-phase synchronous motor exists when the motor is
• What happens if the field winding of the synchronous motor is short-circuited?
• For power factor correction, synchronous motors operate at

Induction Motor MCQs With Explanation 

• In a capacitor start and run the motor the function of the running capacitor in series with the auxiliary winding is to
• A split-phase motor has
• If the capacitor of a single-phase motor is short-circuited
• In a split-phase motor, the running winding should have