Voltage Elevator

Why it matters

Two coils on one iron ring. No moving parts, nothing touching. Yet 11,000 volts walk in one side and 220 walk out the other — the machine that makes the whole grid possible.

The idea in plain words

The ratio that runs the grid. Tap the terms.

Vs ÷ Vp = Ns ÷ Np

11,000 V primary, 5000 turns. How many secondary turns for 220 V?

Ns = 100 turns — your slider's answer

• volts: Vp, Vs — Vp = voltage IN at the primary (the 11 kV line) · Vs = voltage OUT at the secondary (to the town)
• turns: Np, Ns — turn counts of the two coils — p = primary (input) coil, s = secondary (output) coil; the entire design is this ratio
• kind 1: step-up — Ns > Np: more volts, less current (at the power station)
• kind 2: step-down — Ns < Np: fewer volts, more current available (at your street)
• the bridge: iron core — laminated soft iron guides the flux from coil to coil with minimal loss
• Ns = Np × Vs/Vp = 5000 × 220/11000

Predict first

A transformer works on d.c. …

The secondary only sees CHANGING flux. d.c. gives one twitch at switch-on, then silence. Transformers are why the grid runs on a.c.

• not at all — steady current means no changing flux, no induction — correct
• perfectly — volts are volts
• better than on a.c.

What you do

Set the secondary turns so the town gets 210–230 V from the 11 kV line. Overshoot and things catch fire.

Check yourself

An ideal transformer changes voltage but conserves…

Step voltage UP and current steps DOWN in exact proportion — energy stays honest.

A transformer with Np = 200, Ns = 1000 is a…

Ns/Np = 5: whatever enters the primary leaves five times taller.

The motor, the generator and the transformer are, in order…

Three siblings of the same field physics — one spins, one is spun, one just hums and trades volts for amps.

• power: Vp×Ip = Vs×Is — correct
• current
• nothing — it amplifies energy
• step-up transformer (×5) — correct
• step-down transformer
• neither — it needs more coils
• electrical→mechanical, mechanical→electrical, electrical→electrical (changed V) — correct
• all the same machine
• mechanical→electrical, electrical→mechanical, chemical→electrical