Transformers MCQs (Part-2)

What does a transformer change in an electrical system?

A Frequency
B Voltage
C Power
D Current

Which of these types of transformers are designed to operate without oil?

A Distribution transformer
B Oil-filled transformer
C Dry-type transformer
D Power transformer

What causes eddy current loss in a transformer?

A Magnetic flux
B Core vibrations
C Heat generation
D Conduction resistance

What type of transformer is used for electrical isolation between circuits?

A Step-down transformer
B Power transformer
C Autotransformer
D Isolation transformer

Which factor affects the efficiency of a transformer?

A Insulation type
B Core material
C Voltage rating
D Magnetic flux

In a transformer, what happens when the secondary is open-circuited?

A No current in primary
B Secondary voltage drops
C High inrush current
D Current flows freely

How does a transformer reduce energy loss during transmission?

A Improves impedance
B Reduces voltage
C Increases voltage
D Increases current

What is the function of the winding in a transformer?

A Support voltage
B Produce magnetic field
C Reduce losses
D Provide insulation

Which transformer type is most commonly used in power plants for voltage stepping up?

A Step-down transformer
B Distribution transformer
C Isolation transformer
D Power transformer

What type of current causes transformer core magnetization?

A AC
B Pulsed
C DC
D Direct

What is the typical use of an earthing transformer?

A Current boosting
B Impedance matching
C Protection against faults
D Voltage regulation

What does the efficiency of a transformer depend on?

A Voltage regulation
B Load condition
C Core material
D Magnetic field strength

What is the purpose of a step-up transformer?

A Decrease current
B Increase current
C Decrease voltage
D Increase voltage

Which test measures the transformer’s copper loss?

A Impedance test
B Load test
C Short-circuit test
D Open-circuit test

What type of transformer is used to provide electrical isolation without changing voltage?

A Isolation transformer
B Power transformer
C Step-up transformer
D Distribution transformer