Transformers Explained - How transformers work

The video tutorial explains transformers, devices that transfer electrical energy by changing voltage and current. It covers their construction, function, and efficiency, emphasizing the role of alternating current and magnetic fields. The tutorial also discusses power, apparent power, and power factor, and includes examples of transformer calculations and their use in rectifier circuits.

What is the primary function of a transformer?

• To convert electrical energy into mechanical energy

• To transfer electrical energy

• To store electrical energy

• To generate electrical energy

Why do transformers only work with alternating current?

• Because they require a constant magnetic field

• Because they need a changing magnetic field

• Because they operate on direct current

• Because they are used in battery-powered devices

What is the role of the iron core in a transformer?

• To store electrical energy

• To decrease the voltage

• To concentrate the magnetic field

• To increase the resistance

How does a step-up transformer affect voltage and current?

• Increases voltage and decreases current

• Decreases voltage and increases current

• Increases both voltage and current

• Decreases both voltage and current

What is the significance of power factor in transformers?

• It indicates the amount of reactive power

• It determines the size of the transformer

• It affects the efficiency of power transfer

• It measures the voltage output

What is apparent power measured in?

• Joules

• Volt-Amps

• Kilowatts

• Watts

In a transformer, what does a higher number of turns on the secondary coil indicate?

• A decrease in current

• A decrease in voltage

• A step-up transformer

• A step-down transformer

How can you calculate the secondary voltage of a transformer?

• By adding the primary voltage to the turns ratio

• By dividing the primary voltage by the turns ratio

• By subtracting the primary voltage from the turns ratio

• By multiplying the primary voltage by the turns ratio

What happens to the current when the voltage is increased in a transformer?

• The current becomes zero

• The current remains the same

• The current decreases

• The current increases

Why are transformers rated in Volt-Amps instead of Watts?

• Because they only transfer power

• Because they generate power

• Because they convert power

• Because they store power