TRANSFORMERS BASICS Quiz Practice Quiz…

Q: What is the primary function of a transformer?

To change the voltage of an AC supply — Transformers primarily change voltage levels using electromagnetic induction.

Q: What is the core material typically used in transformers?

Laminated steel — Laminated steel minimizes eddy current losses, enhancing efficiency.

Q: The turns ratio of a transformer is defined as:

Number of turns in the primary coil / Number of turns in the secondary coil — Turns ratio directly relates to the voltage transformation.

Q: If the primary voltage is 120V and the secondary voltage is 24V, what type of transformer is it?

Step-down transformer — The secondary voltage is lower than the primary voltage, so it steps down.

Q: In an ideal transformer, what remains constant?

Power — Power is conserved in an ideal transformer (neglecting losses).

Q: What type of loss is minimized by using laminated core?

Eddy current losses — Laminations reduce circulating currents that cause energy loss.

Q: What causes hysteresis loss in a transformer core?

Magnetization and demagnetization of the core — Hysteresis loss is related to energy spent to reverse core magnetization.

Q: What is the core flux in a transformer directly proportional to?

Primary voltage — Core flux is proportional to the applied voltage and inversely proportional to frequency.

Q: Which of the following is NOT a typical application of transformers?

DC to AC conversion — Transformers work with AC, not DC conversion.

Q: What is the purpose of transformer oil?

To cool the transformer and provide insulation — Oil cools and insulates high-voltage transformers.

Question 1 of 15

What is the primary function of a transformer?

Transformers primarily change voltage levels using electromagnetic induction.

Question 2 of 15

What is the core material typically used in transformers?

Laminated steel minimizes eddy current losses, enhancing efficiency.

Question 3 of 15

The turns ratio of a transformer is defined as:

Turns ratio directly relates to the voltage transformation.

Question 4 of 15

If the primary voltage is 120V and the secondary voltage is 24V, what type of transformer is it?

The secondary voltage is lower than the primary voltage, so it steps down.

Question 5 of 15

In an ideal transformer, what remains constant?

Power is conserved in an ideal transformer (neglecting losses).

Question 6 of 15

What type of loss is minimized by using laminated core?

Laminations reduce circulating currents that cause energy loss.

Question 7 of 15

What causes hysteresis loss in a transformer core?

Hysteresis loss is related to energy spent to reverse core magnetization.

Question 8 of 15

What is the core flux in a transformer directly proportional to?

Core flux is proportional to the applied voltage and inversely proportional to frequency.

Question 9 of 15

Which of the following is NOT a typical application of transformers?

Transformers work with AC, not DC conversion.

Question 10 of 15

What is the purpose of transformer oil?

Oil cools and insulates high-voltage transformers.

Question 11 of 15

What is the relationship between primary and secondary currents in an ideal transformer?

Current ratio is the inverse of the turns ratio to conserve power.

Question 12 of 15

A transformer with a turns ratio of 1:1 is called:

An isolation transformer provides voltage transformation of 1:1.

Question 13 of 15

What is leakage flux in a transformer?

Leakage flux doesn't link both windings, reducing efficiency.

Question 14 of 15

What is the main advantage of using a three-phase transformer over a single-phase transformer for power transmission?

Three-phase transformers provide increased power and efficiency.

Question 15 of 15

Which test is used to determine the efficiency and losses of a transformer?

Short circuit tests measure copper losses and open circuit tests measure core losses.

TRANSFORMERS BASICS Quiz