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 450 primary turns and 2700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 450T · ? V · 2700T
2. An ideal step-up transformer has 1350 primary turns and 9450 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 1350T · ? V · 9450T
3. An ideal step-up transformer has 550 primary turns and 1650 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 550T · ? V · 1650T
4. An ideal step-up transformer has 800 primary turns and 4800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 800T · ? V · 4800T
5. An ideal step-up transformer has 700 primary turns and 5600 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 700T · ? V · 5600T
6. An ideal step-up transformer has 950 primary turns and 3800 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 950T · ? V · 3800T
7. An ideal step-up transformer has 350 primary turns and 2100 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 350T · ? V · 2100T
8. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
100V · 1100T · ? V · 8800T
9. An ideal step-up transformer has 1000 primary turns and 6000 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1000T · ? V · 6000T
10. An ideal step-up transformer has 1450 primary turns and 8700 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
160V · 1450T · ? V · 8700T
11. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 1300T · ? V · 10400T
12. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 900T · ? V · 6300T

12 questions · Seed 42 · 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 450 primary turns and 2700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1320 V
Vs = Vp × (Ns ÷ Np) = 220 × (2700 ÷ 450) = 1320 V.
2. An ideal step-up transformer has 1350 primary turns and 9450 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
1470 V
Vs = Vp × (Ns ÷ Np) = 210 × (9450 ÷ 1350) = 1470 V.
3. An ideal step-up transformer has 550 primary turns and 1650 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 200 × (1650 ÷ 550) = 600 V.
4. An ideal step-up transformer has 800 primary turns and 4800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (4800 ÷ 800) = 840 V.
5. An ideal step-up transformer has 700 primary turns and 5600 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
1120 V
Vs = Vp × (Ns ÷ Np) = 140 × (5600 ÷ 700) = 1120 V.
6. An ideal step-up transformer has 950 primary turns and 3800 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 200 × (3800 ÷ 950) = 800 V.
7. An ideal step-up transformer has 350 primary turns and 2100 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (2100 ÷ 350) = 180 V.
8. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 100 × (8800 ÷ 1100) = 800 V.
9. An ideal step-up transformer has 1000 primary turns and 6000 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (6000 ÷ 1000) = 840 V.
10. An ideal step-up transformer has 1450 primary turns and 8700 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
960 V
Vs = Vp × (Ns ÷ Np) = 160 × (8700 ÷ 1450) = 960 V.
11. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
240 V
Vs = Vp × (Ns ÷ Np) = 30 × (10400 ÷ 1300) = 240 V.
12. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
1470 V
Vs = Vp × (Ns ÷ Np) = 210 × (6300 ÷ 900) = 1470 V.

12 questions · Seed 42 · 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 450 primary turns and 2700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
220V · 450T · ? V · 2700T
2. An ideal step-up transformer has 1350 primary turns and 9450 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 1350T · ? V · 9450T
3. An ideal step-up transformer has 550 primary turns and 1650 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 550T · ? V · 1650T
4. An ideal step-up transformer has 800 primary turns and 4800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 800T · ? V · 4800T
5. An ideal step-up transformer has 700 primary turns and 5600 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 700T · ? V · 5600T
6. An ideal step-up transformer has 950 primary turns and 3800 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
200V · 950T · ? V · 3800T
7. An ideal step-up transformer has 350 primary turns and 2100 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 350T · ? V · 2100T
8. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
100V · 1100T · ? V · 8800T
9. An ideal step-up transformer has 1000 primary turns and 6000 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1000T · ? V · 6000T
10. An ideal step-up transformer has 1450 primary turns and 8700 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
160V · 1450T · ? V · 8700T
11. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 1300T · ? V · 10400T
12. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
210V · 900T · ? V · 6300T

12 questions · Seed 42 · 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 450 primary turns and 2700 secondary turns. If the primary voltage is 220 V, what is the secondary voltage?
1320 V
Vs = Vp × (Ns ÷ Np) = 220 × (2700 ÷ 450) = 1320 V.
2. An ideal step-up transformer has 1350 primary turns and 9450 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
1470 V
Vs = Vp × (Ns ÷ Np) = 210 × (9450 ÷ 1350) = 1470 V.
3. An ideal step-up transformer has 550 primary turns and 1650 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
600 V
Vs = Vp × (Ns ÷ Np) = 200 × (1650 ÷ 550) = 600 V.
4. An ideal step-up transformer has 800 primary turns and 4800 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (4800 ÷ 800) = 840 V.
5. An ideal step-up transformer has 700 primary turns and 5600 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
1120 V
Vs = Vp × (Ns ÷ Np) = 140 × (5600 ÷ 700) = 1120 V.
6. An ideal step-up transformer has 950 primary turns and 3800 secondary turns. If the primary voltage is 200 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 200 × (3800 ÷ 950) = 800 V.
7. An ideal step-up transformer has 350 primary turns and 2100 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (2100 ÷ 350) = 180 V.
8. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 100 V, what is the secondary voltage?
800 V
Vs = Vp × (Ns ÷ Np) = 100 × (8800 ÷ 1100) = 800 V.
9. An ideal step-up transformer has 1000 primary turns and 6000 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
840 V
Vs = Vp × (Ns ÷ Np) = 140 × (6000 ÷ 1000) = 840 V.
10. An ideal step-up transformer has 1450 primary turns and 8700 secondary turns. If the primary voltage is 160 V, what is the secondary voltage?
960 V
Vs = Vp × (Ns ÷ Np) = 160 × (8700 ÷ 1450) = 960 V.
11. An ideal step-up transformer has 1300 primary turns and 10400 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
240 V
Vs = Vp × (Ns ÷ Np) = 30 × (10400 ÷ 1300) = 240 V.
12. An ideal step-up transformer has 900 primary turns and 6300 secondary turns. If the primary voltage is 210 V, what is the secondary voltage?
1470 V
Vs = Vp × (Ns ÷ Np) = 210 × (6300 ÷ 900) = 1470 V.

12 questions · Seed 42 · Age guidance, not curriculum certification