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 1500 primary turns and 6000 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 1500T · ? V · 6000T
2. An ideal step-up transformer has 350 primary turns and 1750 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
100V · 350T · ? V · 1750T
3. An ideal step-up transformer has 1250 primary turns and 8750 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1250T · ? V · 8750T
4. An ideal step-up transformer has 350 primary turns and 2450 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 350T · ? V · 2450T
5. An ideal step-up transformer has 900 primary turns and 4500 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 900T · ? V · 4500T
6. An ideal step-up transformer has 450 primary turns and 1800 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 450T · ? V · 1800T
7. An ideal step-up transformer has 200 primary turns and 1000 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
160V · 200T · ? V · 1000T
8. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 900T · ? V · 6300T
9. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 900T · ? V · 6300T
10. An ideal step-up transformer has 600 primary turns and 2400 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
80V · 600T · ? V · 2400T
11. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 1050T · ? V · 6300T
12. An ideal step-up transformer has 900 primary turns and 5400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 900T · ? V · 5400T

12 questions · Seed 50 · 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 1500 primary turns and 6000 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 200 × (6000 ÷ 1500) = 800 V.
2. An ideal step-up transformer has 350 primary turns and 1750 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
500 V
Vs = Vp × (Ns ÷ Np) = 100 × (1750 ÷ 350) = 500 V.
3. An ideal step-up transformer has 1250 primary turns and 8750 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (8750 ÷ 1250) = 980 V.
4. An ideal step-up transformer has 350 primary turns and 2450 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (2450 ÷ 350) = 980 V.
5. An ideal step-up transformer has 900 primary turns and 4500 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
350 V
Vs = Vp × (Ns ÷ Np) = 70 × (4500 ÷ 900) = 350 V.
6. An ideal step-up transformer has 450 primary turns and 1800 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 210 × (1800 ÷ 450) = 840 V.
7. An ideal step-up transformer has 200 primary turns and 1000 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 160 × (1000 ÷ 200) = 800 V.
8. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
210 V
Vs = Vp × (Ns ÷ Np) = 30 × (6300 ÷ 900) = 210 V.
9. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (6300 ÷ 900) = 980 V.
10. An ideal step-up transformer has 600 primary turns and 2400 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
320 V
Vs = Vp × (Ns ÷ Np) = 80 × (2400 ÷ 600) = 320 V.
11. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
1020 V
Vs = Vp × (Ns ÷ Np) = 170 × (6300 ÷ 1050) = 1020 V.
12. An ideal step-up transformer has 900 primary turns and 5400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (5400 ÷ 900) = 180 V.

12 questions · Seed 50 · 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 1500 primary turns and 6000 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 1500T · ? V · 6000T
2. An ideal step-up transformer has 350 primary turns and 1750 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
100V · 350T · ? V · 1750T
3. An ideal step-up transformer has 1250 primary turns and 8750 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1250T · ? V · 8750T
4. An ideal step-up transformer has 350 primary turns and 2450 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 350T · ? V · 2450T
5. An ideal step-up transformer has 900 primary turns and 4500 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 900T · ? V · 4500T
6. An ideal step-up transformer has 450 primary turns and 1800 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 450T · ? V · 1800T
7. An ideal step-up transformer has 200 primary turns and 1000 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
160V · 200T · ? V · 1000T
8. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 900T · ? V · 6300T
9. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 900T · ? V · 6300T
10. An ideal step-up transformer has 600 primary turns and 2400 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
80V · 600T · ? V · 2400T
11. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 1050T · ? V · 6300T
12. An ideal step-up transformer has 900 primary turns and 5400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 900T · ? V · 5400T

12 questions · Seed 50 · 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 1500 primary turns and 6000 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 200 × (6000 ÷ 1500) = 800 V.
2. An ideal step-up transformer has 350 primary turns and 1750 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
500 V
Vs = Vp × (Ns ÷ Np) = 100 × (1750 ÷ 350) = 500 V.
3. An ideal step-up transformer has 1250 primary turns and 8750 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (8750 ÷ 1250) = 980 V.
4. An ideal step-up transformer has 350 primary turns and 2450 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (2450 ÷ 350) = 980 V.
5. An ideal step-up transformer has 900 primary turns and 4500 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
350 V
Vs = Vp × (Ns ÷ Np) = 70 × (4500 ÷ 900) = 350 V.
6. An ideal step-up transformer has 450 primary turns and 1800 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 210 × (1800 ÷ 450) = 840 V.
7. An ideal step-up transformer has 200 primary turns and 1000 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 160 × (1000 ÷ 200) = 800 V.
8. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
210 V
Vs = Vp × (Ns ÷ Np) = 30 × (6300 ÷ 900) = 210 V.
9. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (6300 ÷ 900) = 980 V.
10. An ideal step-up transformer has 600 primary turns and 2400 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
320 V
Vs = Vp × (Ns ÷ Np) = 80 × (2400 ÷ 600) = 320 V.
11. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
1020 V
Vs = Vp × (Ns ÷ Np) = 170 × (6300 ÷ 1050) = 1020 V.
12. An ideal step-up transformer has 900 primary turns and 5400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (5400 ÷ 900) = 180 V.

12 questions · Seed 50 · Age guidance, not curriculum certification