ScienceAges 13-15

Transformer turns & voltage ratio

Use the ideal transformer ratio Vs ÷ Vp = Ns ÷ Np to calculate secondary output voltage. Review suitability for your learners before teaching.

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Worksheet StudioPractice pack · Ages 13-15

Transformer turns & voltage ratio

Take your time. Show your thinking.

1. An ideal step-up transformer has 500 primary turns and 2500 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
120V · 500T · ? V · 2500T
2. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1050T · ? V · 7350T
3. An ideal step-up transformer has 500 primary turns and 3000 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
90V · 500T · ? V · 3000T
4. An ideal step-up transformer has 300 primary turns and 2400 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
150V · 300T · ? V · 2400T
5. An ideal step-up transformer has 150 primary turns and 300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 150T · ? V · 300T
6. An ideal step-up transformer has 400 primary turns and 2800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 400T · ? V · 2800T
7. An ideal step-up transformer has 100 primary turns and 800 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 100T · ? V · 800T
8. An ideal step-up transformer has 1200 primary turns and 9600 secondary turns. If the primary voltage is 110 V, what is the secondary voltage?
110V · 1200T · ? V · 9600T
9. An ideal step-up transformer has 400 primary turns and 800 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
130V · 400T · ? V · 800T
10. An ideal step-up transformer has 250 primary turns and 1000 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 250T · ? V · 1000T
11. An ideal step-up transformer has 1400 primary turns and 2800 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
150V · 1400T · ? V · 2800T
12. An ideal step-up transformer has 750 primary turns and 2250 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
180V · 750T · ? V · 2250T

12 questions · Seed 104729 · Age guidance, not curriculum certification

View the answer key

Worksheet StudioAnswer key · Ages 13-15

Transformer turns & voltage ratio

Answers and reasoning. Review before teaching.

1. An ideal step-up transformer has 500 primary turns and 2500 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 120 × (2500 ÷ 500) = 600 V.
2. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
1330 V
Vs = Vp × (Ns ÷ Np) = 190 × (7350 ÷ 1050) = 1330 V.
3. An ideal step-up transformer has 500 primary turns and 3000 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
540 V
Vs = Vp × (Ns ÷ Np) = 90 × (3000 ÷ 500) = 540 V.
4. An ideal step-up transformer has 300 primary turns and 2400 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
1200 V
Vs = Vp × (Ns ÷ Np) = 150 × (2400 ÷ 300) = 1200 V.
5. An ideal step-up transformer has 150 primary turns and 300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 60 × (300 ÷ 150) = 120 V.
6. An ideal step-up transformer has 400 primary turns and 2800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (2800 ÷ 400) = 980 V.
7. An ideal step-up transformer has 100 primary turns and 800 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1760 V
Vs = Vp × (Ns ÷ Np) = 220 × (800 ÷ 100) = 1760 V.
8. An ideal step-up transformer has 1200 primary turns and 9600 secondary turns. If the primary voltage is 110 V, what is the secondary voltage?
880 V
Vs = Vp × (Ns ÷ Np) = 110 × (9600 ÷ 1200) = 880 V.
9. An ideal step-up transformer has 400 primary turns and 800 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
260 V
Vs = Vp × (Ns ÷ Np) = 130 × (800 ÷ 400) = 260 V.
10. An ideal step-up transformer has 250 primary turns and 1000 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
280 V
Vs = Vp × (Ns ÷ Np) = 70 × (1000 ÷ 250) = 280 V.
11. An ideal step-up transformer has 1400 primary turns and 2800 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
300 V
Vs = Vp × (Ns ÷ Np) = 150 × (2800 ÷ 1400) = 300 V.
12. An ideal step-up transformer has 750 primary turns and 2250 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
540 V
Vs = Vp × (Ns ÷ Np) = 180 × (2250 ÷ 750) = 540 V.

12 questions · Seed 104729 · Age guidance, not curriculum certification

Worksheet StudioPractice pack · Ages 13-15

Transformer turns & voltage ratio

Take your time. Show your thinking.

1. An ideal step-up transformer has 500 primary turns and 2500 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
120V · 500T · ? V · 2500T
2. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1050T · ? V · 7350T
3. An ideal step-up transformer has 500 primary turns and 3000 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
90V · 500T · ? V · 3000T
4. An ideal step-up transformer has 300 primary turns and 2400 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
150V · 300T · ? V · 2400T
5. An ideal step-up transformer has 150 primary turns and 300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 150T · ? V · 300T
6. An ideal step-up transformer has 400 primary turns and 2800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 400T · ? V · 2800T
7. An ideal step-up transformer has 100 primary turns and 800 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 100T · ? V · 800T
8. An ideal step-up transformer has 1200 primary turns and 9600 secondary turns. If the primary voltage is 110 V, what is the secondary voltage?
110V · 1200T · ? V · 9600T
9. An ideal step-up transformer has 400 primary turns and 800 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
130V · 400T · ? V · 800T
10. An ideal step-up transformer has 250 primary turns and 1000 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 250T · ? V · 1000T
11. An ideal step-up transformer has 1400 primary turns and 2800 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
150V · 1400T · ? V · 2800T
12. An ideal step-up transformer has 750 primary turns and 2250 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
180V · 750T · ? V · 2250T

12 questions · Seed 104729 · Age guidance, not curriculum certification

Worksheet StudioAnswer key · Ages 13-15

Transformer turns & voltage ratio

Answers and reasoning. Review before teaching.

1. An ideal step-up transformer has 500 primary turns and 2500 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 120 × (2500 ÷ 500) = 600 V.
2. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
1330 V
Vs = Vp × (Ns ÷ Np) = 190 × (7350 ÷ 1050) = 1330 V.
3. An ideal step-up transformer has 500 primary turns and 3000 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
540 V
Vs = Vp × (Ns ÷ Np) = 90 × (3000 ÷ 500) = 540 V.
4. An ideal step-up transformer has 300 primary turns and 2400 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
1200 V
Vs = Vp × (Ns ÷ Np) = 150 × (2400 ÷ 300) = 1200 V.
5. An ideal step-up transformer has 150 primary turns and 300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 60 × (300 ÷ 150) = 120 V.
6. An ideal step-up transformer has 400 primary turns and 2800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (2800 ÷ 400) = 980 V.
7. An ideal step-up transformer has 100 primary turns and 800 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1760 V
Vs = Vp × (Ns ÷ Np) = 220 × (800 ÷ 100) = 1760 V.
8. An ideal step-up transformer has 1200 primary turns and 9600 secondary turns. If the primary voltage is 110 V, what is the secondary voltage?
880 V
Vs = Vp × (Ns ÷ Np) = 110 × (9600 ÷ 1200) = 880 V.
9. An ideal step-up transformer has 400 primary turns and 800 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
260 V
Vs = Vp × (Ns ÷ Np) = 130 × (800 ÷ 400) = 260 V.
10. An ideal step-up transformer has 250 primary turns and 1000 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
280 V
Vs = Vp × (Ns ÷ Np) = 70 × (1000 ÷ 250) = 280 V.
11. An ideal step-up transformer has 1400 primary turns and 2800 secondary turns. If the primary voltage is 150 V, what is the secondary voltage?
300 V
Vs = Vp × (Ns ÷ Np) = 150 × (2800 ÷ 1400) = 300 V.
12. An ideal step-up transformer has 750 primary turns and 2250 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
540 V
Vs = Vp × (Ns ÷ Np) = 180 × (2250 ÷ 750) = 540 V.

12 questions · Seed 104729 · Age guidance, not curriculum certification