Transformer Fundamentals: Voltage, Current, Turns…

Q: What is the primary function of a transformer?

To change the voltage of an AC supply — Transformers primarily alter voltage levels in AC circuits.

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

Primary voltage to secondary voltage — Turns ratio directly relates to the voltage transformation.

Q: If the primary voltage of a transformer is 120V and the secondary voltage is 24V, what is the turns ratio (assuming ideal transformer)?

5:1 — Turns ratio is primary voltage/secondary voltage = 120/24 = 5:1

Q: In a step-down transformer, the number of turns in the primary winding is _______ than the number of turns in the secondary winding.

Greater — Step-down transformers reduce voltage; thus, primary turns > secondary turns.

Q: How does the current change in a transformer (assuming ideal transformer) if the voltage is stepped up?

Decreases — Power is conserved, so if voltage goes up, current goes down.

Q: If a transformer has a turns ratio of 1:4 and the primary current is 2A, what is the secondary current (assuming ideal transformer)?

8 A — Current ratio is inverse of turns ratio, so I_secondary = 2A * 4 = 8A

Q: Which of the following is true for an ideal transformer?

All of the above. — Ideal transformers have no losses, very high efficiency & infinite permeability

Q: What is the relationship between the primary and secondary voltages and the turns ratio (N)?

Vp/Vs = Np/Ns — Voltage ratio is equal to the turns ratio (primary/secondary)

Q: In a transformer, the energy transfer between the primary and secondary windings occurs through:

Magnetic flux linkage — Energy transfer happens via the mutual magnetic flux.

Q: A transformer with a turns ratio of 2:1 is connected to a 240V AC source on the primary side. What is the secondary voltage?

120V — Secondary voltage = Primary Voltage / turns ratio(2) = 240/2 = 120V

Question 1 of 10

What is the primary function of a transformer?

Transformers primarily alter voltage levels in AC circuits.

Question 2 of 10

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

Turns ratio directly relates to the voltage transformation.

Question 3 of 10

If the primary voltage of a transformer is 120V and the secondary voltage is 24V, what is the turns ratio (assuming ideal transformer)?

Turns ratio is primary voltage/secondary voltage = 120/24 = 5:1

Question 4 of 10

In a step-down transformer, the number of turns in the primary winding is _______ than the number of turns in the secondary winding.

Step-down transformers reduce voltage; thus, primary turns > secondary turns.

Question 5 of 10

How does the current change in a transformer (assuming ideal transformer) if the voltage is stepped up?

Power is conserved, so if voltage goes up, current goes down.

Question 6 of 10

If a transformer has a turns ratio of 1:4 and the primary current is 2A, what is the secondary current (assuming ideal transformer)?

Current ratio is inverse of turns ratio, so I_secondary = 2A * 4 = 8A

Question 7 of 10

Which of the following is true for an ideal transformer?

Ideal transformers have no losses, very high efficiency & infinite permeability

Question 8 of 10

What is the relationship between the primary and secondary voltages and the turns ratio (N)?

Voltage ratio is equal to the turns ratio (primary/secondary)

Question 9 of 10

In a transformer, the energy transfer between the primary and secondary windings occurs through:

Energy transfer happens via the mutual magnetic flux.

Question 10 of 10

A transformer with a turns ratio of 2:1 is connected to a 240V AC source on the primary side. What is the secondary voltage?

Secondary voltage = Primary Voltage / turns ratio(2) = 240/2 = 120V

Transformer Fundamentals: Voltage, Current, Turns Ratio Quiz