Single-Phase Transformers Quiz

What is the primary function of a transformer?

• To store electrical energy

• To increase the frequency of electrical energy

• To transmit electrical energy between systems with different voltages

• To convert AC to DC

Which type of transformer is most commonly used in residential systems?

• Protection transformers

• Instrumentation transformers

• Single-phase transformers

• Three-phase transformers

What are the two main windings in a transformer called?

• Primary and secondary

• Inductive and capacitive

• Input and output

• High voltage and low voltage

What is the purpose of the no-load test?

• To calculate the voltage drop

• To assess the short-circuit impedance

• To determine the transformation ratio and core losses

• To measure the efficiency of the transformer

What does the transformation ratio of a transformer depend on?

• The load current

• The number of turns of the windings

• The type of core material

• The frequency of the input voltage

What is the main cooling medium used in transformers?

• Solid materials

• Gas

• Air and mineral oil

• Water

What is the formula for the efficiency of a transformer?

• η = P₁ / P₂

• η = P₂ / (P₂ + Pfe + Pcu) * 100

• η = P₂ / P₁

• η = (Pcu + Pfe) / P₂

What happens to the primary current when a load is connected to the secondary winding?

• It increases

• It becomes zero

• It remains the same

• It decreases

What type of connection is represented by 'Y' for the primary and 'y' for the secondary?

• Star connection

• Zig-Zag connection

• Parallel connection

• Delta connection

What is the purpose of the short-circuit test?

• To measure core losses

• To determine the transformation ratio

• To calculate the efficiency

• To assess the impedance and copper losses