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 250 primary turns and 1250 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
120V · 250T · ? V · 1250T
2. An ideal step-up transformer has 950 primary turns and 5700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 950T · ? V · 5700T
3. An ideal step-up transformer has 1500 primary turns and 12000 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
80V · 1500T · ? V · 12000T
4. An ideal step-up transformer has 550 primary turns and 2200 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
130V · 550T · ? V · 2200T
5. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 1300T · ? V · 10400T
6. An ideal step-up transformer has 500 primary turns and 3500 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 500T · ? V · 3500T
7. An ideal step-up transformer has 600 primary turns and 1200 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 600T · ? V · 1200T
8. An ideal step-up transformer has 700 primary turns and 4200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 700T · ? V · 4200T
9. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 20 V, what is the secondary voltage?
20V · 350T · ? V · 1400T
10. An ideal step-up transformer has 1000 primary turns and 8000 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
180V · 1000T · ? V · 8000T
11. An ideal step-up transformer has 1050 primary turns and 2100 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1050T · ? V · 2100T
12. An ideal step-up transformer has 1400 primary turns and 9800 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 1400T · ? V · 9800T

12 questions · Seed 52 · 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 250 primary turns and 1250 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 120 × (1250 ÷ 250) = 600 V.
2. An ideal step-up transformer has 950 primary turns and 5700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1320 V
Vs = Vp × (Ns ÷ Np) = 220 × (5700 ÷ 950) = 1320 V.
3. An ideal step-up transformer has 1500 primary turns and 12000 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
640 V
Vs = Vp × (Ns ÷ Np) = 80 × (12000 ÷ 1500) = 640 V.
4. An ideal step-up transformer has 550 primary turns and 2200 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
520 V
Vs = Vp × (Ns ÷ Np) = 130 × (2200 ÷ 550) = 520 V.
5. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1840 V
Vs = Vp × (Ns ÷ Np) = 230 × (10400 ÷ 1300) = 1840 V.
6. An ideal step-up transformer has 500 primary turns and 3500 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1610 V
Vs = Vp × (Ns ÷ Np) = 230 × (3500 ÷ 500) = 1610 V.
7. An ideal step-up transformer has 600 primary turns and 1200 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 60 × (1200 ÷ 600) = 120 V.
8. An ideal step-up transformer has 700 primary turns and 4200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (4200 ÷ 700) = 840 V.
9. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 20 V, what is the secondary voltage?
80 V
Vs = Vp × (Ns ÷ Np) = 20 × (1400 ÷ 350) = 80 V.
10. An ideal step-up transformer has 1000 primary turns and 8000 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
1440 V
Vs = Vp × (Ns ÷ Np) = 180 × (8000 ÷ 1000) = 1440 V.
11. An ideal step-up transformer has 1050 primary turns and 2100 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
380 V
Vs = Vp × (Ns ÷ Np) = 190 × (2100 ÷ 1050) = 380 V.
12. An ideal step-up transformer has 1400 primary turns and 9800 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
1190 V
Vs = Vp × (Ns ÷ Np) = 170 × (9800 ÷ 1400) = 1190 V.

12 questions · Seed 52 · 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 250 primary turns and 1250 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
120V · 250T · ? V · 1250T
2. An ideal step-up transformer has 950 primary turns and 5700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 950T · ? V · 5700T
3. An ideal step-up transformer has 1500 primary turns and 12000 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
80V · 1500T · ? V · 12000T
4. An ideal step-up transformer has 550 primary turns and 2200 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
130V · 550T · ? V · 2200T
5. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 1300T · ? V · 10400T
6. An ideal step-up transformer has 500 primary turns and 3500 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 500T · ? V · 3500T
7. An ideal step-up transformer has 600 primary turns and 1200 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 600T · ? V · 1200T
8. An ideal step-up transformer has 700 primary turns and 4200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 700T · ? V · 4200T
9. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 20 V, what is the secondary voltage?
20V · 350T · ? V · 1400T
10. An ideal step-up transformer has 1000 primary turns and 8000 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
180V · 1000T · ? V · 8000T
11. An ideal step-up transformer has 1050 primary turns and 2100 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1050T · ? V · 2100T
12. An ideal step-up transformer has 1400 primary turns and 9800 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 1400T · ? V · 9800T

12 questions · Seed 52 · 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 250 primary turns and 1250 secondary turns. If the primary voltage is 120 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 120 × (1250 ÷ 250) = 600 V.
2. An ideal step-up transformer has 950 primary turns and 5700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1320 V
Vs = Vp × (Ns ÷ Np) = 220 × (5700 ÷ 950) = 1320 V.
3. An ideal step-up transformer has 1500 primary turns and 12000 secondary turns. If the primary voltage is 80 V, what is the secondary voltage?
640 V
Vs = Vp × (Ns ÷ Np) = 80 × (12000 ÷ 1500) = 640 V.
4. An ideal step-up transformer has 550 primary turns and 2200 secondary turns. If the primary voltage is 130 V, what is the secondary voltage?
520 V
Vs = Vp × (Ns ÷ Np) = 130 × (2200 ÷ 550) = 520 V.
5. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1840 V
Vs = Vp × (Ns ÷ Np) = 230 × (10400 ÷ 1300) = 1840 V.
6. An ideal step-up transformer has 500 primary turns and 3500 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1610 V
Vs = Vp × (Ns ÷ Np) = 230 × (3500 ÷ 500) = 1610 V.
7. An ideal step-up transformer has 600 primary turns and 1200 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 60 × (1200 ÷ 600) = 120 V.
8. An ideal step-up transformer has 700 primary turns and 4200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (4200 ÷ 700) = 840 V.
9. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 20 V, what is the secondary voltage?
80 V
Vs = Vp × (Ns ÷ Np) = 20 × (1400 ÷ 350) = 80 V.
10. An ideal step-up transformer has 1000 primary turns and 8000 secondary turns. If the primary voltage is 180 V, what is the secondary voltage?
1440 V
Vs = Vp × (Ns ÷ Np) = 180 × (8000 ÷ 1000) = 1440 V.
11. An ideal step-up transformer has 1050 primary turns and 2100 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
380 V
Vs = Vp × (Ns ÷ Np) = 190 × (2100 ÷ 1050) = 380 V.
12. An ideal step-up transformer has 1400 primary turns and 9800 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
1190 V
Vs = Vp × (Ns ÷ Np) = 170 × (9800 ÷ 1400) = 1190 V.

12 questions · Seed 52 · Age guidance, not curriculum certification