Numerical answer · +4 / −1
A transformer has 100 primary turns and 500 secondary turns. If primary voltage is 220 V, secondary voltage (in V) is:
Answer and solution
Answer 1100
Solution
Physics sir · 3 steps
In an ideal transformer, volts per turn is the same on both sides, so voltage scales with the turns.
- Same flux, both coils. The same changing magnetic flux links every turn of the primary and the secondary. So each turn has the same induced emf, and the voltage across a coil is proportional to its number of turns.
Vₛ/Vₚ = Nₛ/Nₚ
- Put in numbers. Nₛ/Nₚ = 500/100 = 5, so Vₛ = 5 × 220 V.
- So. Vₛ = 1100 V. More turns on the secondary means this is a step-up transformer, and the answer is 1100.
The common slip: 44. Flipping the ratio to Nₚ/Nₛ gives 44 V, which would be a step-down result even though the secondary has more turns.
The idea to keep. Voltage goes with the turns ratio: more secondary turns means step-up. Current goes the other way, because the power VI stays the same in an ideal transformer.
Answer from the NTA final answer key. Solution by PrepWiser.