Transformers and Their Functions

The video tutorial explains how transformers work, focusing on their components, such as primary and secondary coils linked by an iron core. It describes how alternating current creates a magnetic field, which induces voltage in the secondary coil. The tutorial covers the transformer equation, showing how the number of turns affects voltage. Practical examples illustrate step-up and step-down transformers. Finally, it discusses transformers' role in the National Grid, highlighting their importance in reducing power loss and improving efficiency.

What is the primary difference between a step-up and a step-down transformer?

• The type of current they use

• The number of turns on the primary and secondary coils

• The size of the transformer

• The material of the core

Why is an iron core used in transformers?

• Iron is cheaper than other metals

• Iron is a good conductor of electricity

• Iron is a magnetic metal

• Iron is non-magnetic

How does an alternating current affect the magnetic field in a transformer?

• It creates a constant magnetic field

• It creates a static magnetic field

• It has no effect on the magnetic field

• It creates an alternating magnetic field

What is the purpose of the transformer equation?

• To find the ratio of turns and voltage

• To determine the type of transformer

• To calculate the efficiency of a transformer

• To measure the power loss in a transformer

If a transformer has the same number of turns on both coils, what will be the voltage output?

• The voltage will be doubled

• The voltage will be halved

• The voltage will remain the same

• The voltage will be zero

In a step-up transformer, if the secondary coil has twice as many turns as the primary, what happens to the voltage?

• The voltage is halved

• The voltage is reduced to zero

• The voltage remains the same

• The voltage is doubled

What happens to the voltage in a step-down transformer with more turns on the primary coil?

• The voltage remains constant

• The voltage decreases

• The voltage becomes zero

• The voltage increases

How does stepping up the voltage in the National Grid help reduce power loss?

• It increases the current

• It decreases the current

• It keeps the current constant

• It has no effect on the current

What is the typical voltage stepped down to for household use from the National Grid?

• 12 Volts

• 110 Volts

• 240 Volts

• 230 Volts

Why is it inefficient to transmit electricity at 230 volts across long distances?

• It requires more transformers

• It is not possible to transmit at this voltage

• It is more expensive

• It causes high power loss due to high current