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 950 primary turns and 5700 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 950T · ? V · 5700T
2. An ideal step-up transformer has 1150 primary turns and 9200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1150T · ? V · 9200T
3. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 1050T · ? V · 6300T
4. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 1050T · ? V · 7350T
5. An ideal step-up transformer has 200 primary turns and 600 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 200T · ? V · 600T
6. An ideal step-up transformer has 1100 primary turns and 2200 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1100T · ? V · 2200T
7. An ideal step-up transformer has 850 primary turns and 6800 secondary turns. If the primary voltage is 40 V, what is the secondary voltage?
40V · 850T · ? V · 6800T
8. An ideal step-up transformer has 100 primary turns and 700 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 100T · ? V · 700T
9. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 1100T · ? V · 8800T
10. An ideal step-up transformer has 1450 primary turns and 10150 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1450T · ? V · 10150T
11. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
90V · 350T · ? V · 1400T
12. An ideal step-up transformer has 1300 primary turns and 5200 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 1300T · ? V · 5200T

12 questions · Seed 104730 · 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 950 primary turns and 5700 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (5700 ÷ 950) = 180 V.
2. An ideal step-up transformer has 1150 primary turns and 9200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
1120 V
Vs = Vp × (Ns ÷ Np) = 140 × (9200 ÷ 1150) = 1120 V.
3. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
360 V
Vs = Vp × (Ns ÷ Np) = 60 × (6300 ÷ 1050) = 360 V.
4. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
490 V
Vs = Vp × (Ns ÷ Np) = 70 × (7350 ÷ 1050) = 490 V.
5. An ideal step-up transformer has 200 primary turns and 600 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
510 V
Vs = Vp × (Ns ÷ Np) = 170 × (600 ÷ 200) = 510 V.
6. An ideal step-up transformer has 1100 primary turns and 2200 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
380 V
Vs = Vp × (Ns ÷ Np) = 190 × (2200 ÷ 1100) = 380 V.
7. An ideal step-up transformer has 850 primary turns and 6800 secondary turns. If the primary voltage is 40 V, what is the secondary voltage?
320 V
Vs = Vp × (Ns ÷ Np) = 40 × (6800 ÷ 850) = 320 V.
8. An ideal step-up transformer has 100 primary turns and 700 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1610 V
Vs = Vp × (Ns ÷ Np) = 230 × (700 ÷ 100) = 1610 V.
9. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
480 V
Vs = Vp × (Ns ÷ Np) = 60 × (8800 ÷ 1100) = 480 V.
10. An ideal step-up transformer has 1450 primary turns and 10150 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (10150 ÷ 1450) = 980 V.
11. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
360 V
Vs = Vp × (Ns ÷ Np) = 90 × (1400 ÷ 350) = 360 V.
12. An ideal step-up transformer has 1300 primary turns and 5200 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 30 × (5200 ÷ 1300) = 120 V.

12 questions · Seed 104730 · 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 950 primary turns and 5700 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 950T · ? V · 5700T
2. An ideal step-up transformer has 1150 primary turns and 9200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1150T · ? V · 9200T
3. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 1050T · ? V · 6300T
4. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
70V · 1050T · ? V · 7350T
5. An ideal step-up transformer has 200 primary turns and 600 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
170V · 200T · ? V · 600T
6. An ideal step-up transformer has 1100 primary turns and 2200 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
190V · 1100T · ? V · 2200T
7. An ideal step-up transformer has 850 primary turns and 6800 secondary turns. If the primary voltage is 40 V, what is the secondary voltage?
40V · 850T · ? V · 6800T
8. An ideal step-up transformer has 100 primary turns and 700 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
230V · 100T · ? V · 700T
9. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
60V · 1100T · ? V · 8800T
10. An ideal step-up transformer has 1450 primary turns and 10150 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
140V · 1450T · ? V · 10150T
11. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
90V · 350T · ? V · 1400T
12. An ideal step-up transformer has 1300 primary turns and 5200 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
30V · 1300T · ? V · 5200T

12 questions · Seed 104730 · 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 950 primary turns and 5700 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
180 V
Vs = Vp × (Ns ÷ Np) = 30 × (5700 ÷ 950) = 180 V.
2. An ideal step-up transformer has 1150 primary turns and 9200 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
1120 V
Vs = Vp × (Ns ÷ Np) = 140 × (9200 ÷ 1150) = 1120 V.
3. An ideal step-up transformer has 1050 primary turns and 6300 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
360 V
Vs = Vp × (Ns ÷ Np) = 60 × (6300 ÷ 1050) = 360 V.
4. An ideal step-up transformer has 1050 primary turns and 7350 secondary turns. If the primary voltage is 70 V, what is the secondary voltage?
490 V
Vs = Vp × (Ns ÷ Np) = 70 × (7350 ÷ 1050) = 490 V.
5. An ideal step-up transformer has 200 primary turns and 600 secondary turns. If the primary voltage is 170 V, what is the secondary voltage?
510 V
Vs = Vp × (Ns ÷ Np) = 170 × (600 ÷ 200) = 510 V.
6. An ideal step-up transformer has 1100 primary turns and 2200 secondary turns. If the primary voltage is 190 V, what is the secondary voltage?
380 V
Vs = Vp × (Ns ÷ Np) = 190 × (2200 ÷ 1100) = 380 V.
7. An ideal step-up transformer has 850 primary turns and 6800 secondary turns. If the primary voltage is 40 V, what is the secondary voltage?
320 V
Vs = Vp × (Ns ÷ Np) = 40 × (6800 ÷ 850) = 320 V.
8. An ideal step-up transformer has 100 primary turns and 700 secondary turns. If the primary voltage is 230 V, what is the secondary voltage?
1610 V
Vs = Vp × (Ns ÷ Np) = 230 × (700 ÷ 100) = 1610 V.
9. An ideal step-up transformer has 1100 primary turns and 8800 secondary turns. If the primary voltage is 60 V, what is the secondary voltage?
480 V
Vs = Vp × (Ns ÷ Np) = 60 × (8800 ÷ 1100) = 480 V.
10. An ideal step-up transformer has 1450 primary turns and 10150 secondary turns. If the primary voltage is 140 V, what is the secondary voltage?
980 V
Vs = Vp × (Ns ÷ Np) = 140 × (10150 ÷ 1450) = 980 V.
11. An ideal step-up transformer has 350 primary turns and 1400 secondary turns. If the primary voltage is 90 V, what is the secondary voltage?
360 V
Vs = Vp × (Ns ÷ Np) = 90 × (1400 ÷ 350) = 360 V.
12. An ideal step-up transformer has 1300 primary turns and 5200 secondary turns. If the primary voltage is 30 V, what is the secondary voltage?
120 V
Vs = Vp × (Ns ÷ Np) = 30 × (5200 ÷ 1300) = 120 V.

12 questions · Seed 104730 · Age guidance, not curriculum certification