Transformer Concepts and Calculations

This video tutorial explains the function of transformers in changing the potential difference of an electricity supply. It covers the use of step-up and step-down transformers and introduces two key equations that relate potential difference, current, and the number of turns on the coils. The video includes example problems to calculate output potential difference and current, providing a practical understanding of the concepts discussed.

What is the primary function of a transformer in an electrical circuit?

• To generate electricity

• To change the potential difference

• To store electrical energy

• To convert AC to DC

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

• It decreases the potential difference

• It increases the potential difference

• It keeps the potential difference constant

• It converts potential difference to current

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

• More turns on the secondary coil

• Less turns on the secondary coil

• No turns on the secondary coil

• Equal turns on both coils

What does the symbol 'Vp' represent in transformer equations?

• Output current

• Output potential difference

• Input potential difference

• Number of turns on the secondary coil

Which equation would you use if you only have potential difference and number of turns data?

• The equation involving resistance

• The equation involving current

• The equation involving power

• The equation involving potential difference and turns

If a transformer has 18 turns on the primary coil and 54 on the secondary, what is the output potential difference if the input is 45 volts?

• 135 volts

• 90 volts

• 15 volts

• 45 volts

What is the first step in solving a transformer problem involving potential difference?

• Ignore the number of turns

• List known values and what you need to find

• Directly calculate the output

• Guess the output

If the input current of a transformer is 12 amps, what is the output current given the output potential difference is 135 volts?

• 8 amps

• 16 amps

• 12 amps

• 4 amps

Which equation is used to calculate the output current of a transformer?

• The equation involving power

• The equation involving resistance

• The equation involving current and potential difference

• The equation involving potential difference and turns

What is the final step in calculating the output current of a transformer?

• Add the input and output currents

• Multiply both sides by the input current

• Divide both sides by the output potential difference

• Subtract the input current from the output current