USING TRANSFORMERS TO CHANGE VOLTAGES
3 marks · NormalThe table shows data for four transformers. Complete the table by filling in the missing voltages using the transformer equation.
| Primary voltage (V) | Secondary voltage (V) | Primary turns | Secondary turns |
|---|---|---|---|
| 15 | 300 | 600 | |
| 9 | 450 | 150 | |
| 6 | 80 | 40 |
Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.
Show answer
Must show: first row: 30, second row: 27, third row: 3
Common mistakes: Mixing up primary and secondary coils; Arithmetic error
Show mark scheme and worked solution
Marking points
A1 · 1 mark · Correctly calculates secondary voltage in row 1: 30 V
A2 · 1 mark · Correctly calculates primary voltage in row 2: 27 V
A3 · 1 mark · Correctly calculates secondary voltage in row 3: 3 V
Worked solution
Apply for each row:
| Primary voltage (V) | Secondary voltage (V) | Primary turns | Secondary turns |
|---|---|---|---|
| 15 | 30 | 300 | 600 |
| 27 | 9 | 450 | 150 |
| 6 | 3 | 80 | 40 |