Understanding Input and Output Currents in Transformers and Their Practical Applications

The video tutorial explains how transformers work, focusing on the relationship between the number of turns in the primary and secondary coils and their effect on input and output currents. It covers the definition of electrical power, the efficiency of transformers, and the equations that relate power, current, and potential difference. The tutorial also distinguishes between step up and step down transformers and their applications in the National Grid, highlighting how they help reduce power loss during electricity transmission.

What is the primary function of a transformer?

• To store electrical energy

• To increase or decrease the potential difference of an AC supply

• To convert direct current to alternating current

• To measure electrical resistance

How is electrical power defined in the context of transformers?

• As the energy stored in a magnetic field

• As the energy transferred by a circuit per second

• As the voltage drop across a resistor

• As the resistance of a circuit

What happens to the current in a step-up transformer?

• It increases

• It remains the same

• It fluctuates

• It decreases

In a step-down transformer, how does the number of turns on the primary coil compare to the secondary coil?

• The primary coil has more turns

• The primary coil has fewer turns

• Both coils have the same number of turns

• The number of turns varies randomly

How does a step-up transformer affect the potential difference?

• It reverses the potential difference

• It keeps the potential difference constant

• It increases the potential difference

• It decreases the potential difference

What is the main reason for using a high potential difference in the National Grid?

• To increase the current in the cables

• To decrease the voltage for home use

• To reduce power loss due to resistive heating

• To increase the speed of electricity

What is the role of step-down transformers in the National Grid?

• To decrease the potential difference for homes and businesses

• To increase the potential difference for factories

• To maintain a constant potential difference

• To convert AC to DC