Star Delta Transformation mcqs in network theorem
The star-delta transformation preserves the __ of the circuit.
a) Power factor
b) Voltage
c) Current
d) Resistance
Answer: c) Current
Explanation: The star-delta transformation preserves the current in the circuit. The total current remains the same before and after the transformation.
The star-delta transformation is applicable to circuits containing __.
a) Only resistors
b) Only capacitors
c) Only inductors
d) Resistors, capacitors, and inductors
Answer: d) Resistors, capacitors, and inductors
Explanation: The star-delta transformation can be applied to circuits containing resistors, capacitors, and inductors or any combination thereof.
The star-delta transformation is most commonly used in __ circuits.
a) Single-phase
b) Three-phase
c) Digital communication
d) Audio
Answer: b) Three-phas
Explanation: The star-delta transformation is most commonly used in three-phase circuits to convert between star and delta configurations.
The star-delta transformation is based on the concept of __.
a) Kirchhoff’s Laws
b) Faraday’s Law
c) Ampere’s Law
d) Ohm’s Law
Answer: a) Kirchhoff’s Laws
Explanation: The star-delta transformation is based on the application of Kirchhoff’s Laws to simplify circuit analysis.
The number of impedances in the star configuration is __ the number of impedances in the delta configuration.
a) Equal to
b) Less than
c) Greater than
d) Unrelated to
Answer: b) Less than
Explanation: The number of impedances in the star configuration is less than the number of impedances in the delta configuration.
The star-delta transformation can be used to convert a _ circuit to a _ circuit.
a) Parallel, series
b) Series, parallel
c) Capacitive, inductive
d) None of the above
Answer: b) Series, parallel
Explanation: The star-delta transformation can be used to convert a series circuit to a parallel circuit.
The star-delta transformation is used to simplify calculations involving __.
a) Power factor correction
b) Voltage regulation
c) Power dissipation
d) Complex impedances
Answer: d) Complex impedances
Explanation: The star-delta transformation is used to simplify calculations involving complex impedances in AC circuits.
In the star-delta transformation, the impedance in the delta configuration is equal to the impedance in the star configuration __.
a) Divided by √3
b) Multiplied by √3
c) Divided by 3
d) Multiplied by 3
Answer: a) Divided by √3
Explanation: In the star-delta transformation, the impedance in the delta configuration is equal to the impedance in the star configuration divided by √3.
The star-delta transformation is an example of a __ transformation.
a) Voltage-current
b) Current-voltage
c) Impedance-resistance
d) Resistance-impedance
Answer: a) Voltage-current
Explanation: The star-delta transformation is an example of a voltage-current transformation, as it involves converting between voltage and current representations.
The star-delta transformation simplifies circuit analysis by reducing the number of __ in the circuit.
a) Resistors
b) Inductors
c) Capacitors
d) Unknown variables
Answer: d) Unknown variables
Explanation: The star-delta transformation simplifies circuit analysis by reducing the number of unknown variables in the circuit.
The star-delta transformation is reversible, meaning that a delta configuration can be converted back to a star configuration.
a) True
b) False
Answer: a) True
Explanation: The star-delta transformation is reversible, and a delta configuration can be converted back to a star configuration using the same principles.
The star-delta transformation is particularly beneficial for analyzing circuits with __.
a) High voltage levels
b) High current levels
c) Balanced loads
d) Unbalanced loads
Answer: c) Balanced loads
Explanation: The star-delta transformation is particularly beneficial for analyzing circuits with balanced loads, where the impedances are evenly distributed.
The star-delta transformation is commonly used in __ systems.
a) Power distribution
b) Telecommunications
c) Control systems
d) All of the above
Answer: d) All of the above
Explanation: The star-delta transformation is commonly used in power distribution systems, telecommunications, control systems, and various other applications.
The star-delta transformation is commonly applied in __ circuits.
a) AC circuits
b) DC circuits
c) Series circuits
d) Parallel circuits
Answer: a) AC circuits
Explanation: The star-delta transformation is commonly applied in AC circuits to simplify calculations and analysis.
In the star-delta transformation, the impedance values in the star configuration are related to the impedance values in the delta configuration by a multiplication factor of __.
a) √3
b) 1/√3
c) 3
d) 1/3
Answer: b) 1/√3
Explanation: In the star-delta transformation, the impedance values in the star configuration are related to the impedance values in the delta configuration by a multiplication factor of 1/√3.